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Background: Performing physical activity may provide analgesic benefit, although this effect is more established for noncancer pain rather than cancer pain. The relationship between physical activity and pain outcomes in adults with and without a history of cancer was examined., Methods: Totals of 51,439 adults without a cancer history and 10,651 adults with a cancer history from the Cancer Prevention Study II Nutrition Cohort were included. Exposures included self-reported moderate to vigorous physical activity (MVPA) as well as 2-year change in MVPA. Pain outcomes included pain intensity (primary outcome) and analgesic use (secondary outcome)., Results: MVPA was inversely associated with pain intensity for adults with (odds ratio [OR], 0.84 [≥15 metabolic equivalent of task (MET) h/week vs. <7.5 MET h/week]; 95% confidence interval [CI], 0.76-0.93) and without (OR, 0.79; 95% CI, 0.75-0.82) a history of cancer. Compared to remaining inactive, participants who became sufficiently active (cancer: OR, 0.76; 95% CI, 0.68-0.86; no cancer: OR, 0.73; 95% CI, 0.69-0.77), became inactive (cancer: OR, 0.79; 95% CI, 0.71-0.88; no cancer: OR, 0.84; 95% CI, 0.80-0.89), or remained sufficiently active (cancer: OR, 0.66; 95% CI, 0.60-0.72; no cancer: OR, 0.62; 95% CI, 0.60-0.65) also reported less pain. Physical activity was not related to analgesic use., Conclusions: The relationship between physical activity and pain intensity was not substantially different between people with and without a history of cancer. Cancer survivors who perform more activity, or who increase their activity, may experience less pain than cancer survivors who consistently perform less., Plain Language Summary: People who have had cancer often experience ongoing pain. Being physically active may help reduce the intensity of the pain they experience., (© 2024 The Authors. Cancer published by Wiley Periodicals LLC on behalf of American Cancer Society.)

Background: Pre-diagnostic physical activity is reported to improve survival for women with breast cancer. However, studies of pre-diagnostic exposures and cancer survival are susceptible to bias, made clear when applying a target trial framework. We investigated the impact of selection bias, immortal time bias, confounding and bias due to inappropriate adjustment for post-exposure variables in a systematic review and meta-analysis of pre-diagnostic physical activity and survival after breast cancer., Methods: Medline, Embase and Emcare were searched from inception to November 2021 for studies examining pre-diagnostic physical activity and overall or breast cancer-specific survival for women with breast cancer. Random-effects meta-analysis was used to estimate pooled hazard ratios (HRs) and 95% confidence intervals (CIs) comparing highest versus lowest pre-diagnostic physical activity. Subgroup meta-analyses were used to compare HRs of studies with and without different biases. ROBINS-E was used to assess risk of bias., Results: We included 22 studies. Women with highest versus lowest pre-diagnostic physical activity had higher overall and breast cancer-specific survival across most analyses. The overall risk of bias was high. We observed marked differences in estimated HRs between studies that did and did not adjust for post-exposure variables or have immortal time bias. All studies were at risk of selection bias due to participants becoming eligible for study when they have survived to post-exposure events (e.g., breast cancer diagnosis). Insufficient studies were available to investigate confounding., Conclusion: Biases can substantially change effect estimates. Due to misalignment of treatment assignment (before diagnosis), eligibility (survival to post-exposure events) and start of follow-up, bias is difficult to avoid. It is difficult to lend a causal interpretation to effect estimates from studies of pre-diagnostic physical activity and survival after cancer. Biased effect estimates that are difficult to interpret may be less useful for clinical or public health policy applications., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Brigid Lynch reports financial support was provided by Victorian Cancer Agency. Frances Albers reports financial support was provided by Commonwealth of Australia. Ziyu Wang reports financial support was provided by China Scholarship Council. Brigid Lynch reports a relationship with SciLifeLab that includes: travel reimbursement., (Copyright © 2024. Published by Elsevier Ltd.)

Purpose: Physical activity can provide analgesic benefit but its effect on cancer-related pain is unclear. This review synthesised and appraised the evidence for the effect of physical activity on pain in people living with or beyond cancer., Methods: A systematic search of Ovid Medline and Embase was performed to identify randomised controlled trials (RCTs), randomised cross-over studies (RXTs), and prospective observational studies that examined physical activity and pain outcomes in adults living with or beyond cancer. Meta-analyses were performed to generate effect estimates. Risk of bias was assessed, and the GRADE system was used to assess evidence quality., Results: One hundred twenty-one studies (n = 13,806), including 102 RCTs, 6 RXTs, and 13 observational studies, met the criteria for inclusion. Meta-analyses of RCTs identified a decrease in pain intensity (n = 3734; standardised mean difference (SMD) - 0.30; 95% confidence interval (CI) - 0.45, - 0.15) and bodily pain (n = 1170; SMD 0.28; 95% CI 0.01, 0.56) but not pain interference (n = 207; SMD - 0.13, 95% CI - 0.42, 0.15) following physical activity interventions. Individual studies also identified a reduction in pain sensitivity but not analgesic use, although meta-analysis was not possible for these outcomes. High heterogeneity between studies, low certainty in some effect estimates, and possible publication bias meant that evidence quality was graded as very low to low., Conclusion: Physical activity may decrease pain in people living with and beyond cancer; however, high heterogeneity limits the ability to generalise this finding to all people with cancer or to specific types of cancer-related pain., (© 2024. The Author(s).)

Background: There is increasing evidence for the relationship between physical activity (PA), sedentary behaviour and mental health. Limited data exists on sex-specific associations. We aimed to identify associations between PA dose and domain and television time with psychological distress, including sex-stratified models., Methods: A total of 22,176 adults from the Melbourne Collaborative Cohort Study follow-up 2 cohort (2003-2007) participated in this cross-sectional study. Occupational, household, transport, leisure PA, hours watching television and psychological distress were assessed. Restricted cubic splines were used to examine the relationships between PA domains, television viewing time and psychological distress., Results: The relationships between PA and psychological distress were non-linear (p < 0.05) and differed by PA domain. There were dose-dependent, inverse associations between distress with transport (B[95% CI] = -0.39[-0.49, -0.30]) and leisure PA (B[95% CI] = -0.35[-0.46, -0.25]). The effect estimates for transport and leisure PA with distress were larger for women. For household domain, a U-shaped curve with an elongated tail was seen. Median PA was associated with lower distress compared with lower quantities (B[95% CI] = -0.12[-0.22, -0.03]); however, this association was not evident with increasing household PA. There were no clear associations between occupational PA and distress. Higher television viewing was associated with higher distress (B[95% CI] = 0.16[0.02, 0.30])., Conclusions: Increasing PA and reducing television viewing may contribute to reduced psychological distress, particularly in women. Future interventions should incorporate leisure and transport PA and decrease television viewing to assess the impact on mental health., (© 2022. The Author(s).)

Background: Physical activity (PA) surveillance, policy, and research efforts need to be periodically appraised to gain insight into national and global capacities for PA promotion. The aim of this paper was to assess the status and trends in PA surveillance, policy, and research in 164 countries., Methods: We used data from the Global Observatory for Physical Activity (GoPA!) 2015 and 2020 surveys. Comprehensive searches were performed for each country to determine the level of development of their PA surveillance, policy, and research, and the findings were verified by the GoPA! Country Contacts. Trends were analyzed based on the data available for both survey years., Results: The global 5-year progress in all 3 indicators was modest, with most countries either improving or staying at the same level. PA surveillance, policy, and research improved or remained at a high level in 48.1%, 40.6%, and 42.1% of the countries, respectively. PA surveillance, policy, and research scores decreased or remained at a low level in 8.3%, 15.8%, and 28.6% of the countries, respectively. The highest capacity for PA promotion was found in Europe, the lowest in Africa and low- and lower-middle-income countries. Although a large percentage of the world's population benefit from at least some PA policy, surveillance, and research efforts in their countries, 49.6 million people are without PA surveillance, 629.4 million people are without PA policy, and 108.7 million live in countries without any PA research output. A total of 6.3 billion people or 88.2% of the world's population live in countries where PA promotion capacity should be significantly improved., Conclusion: Despite PA is essential for health, there are large inequalities between countries and world regions in their capacity to promote PA. Coordinated efforts are needed to reduce the inequalities and improve the global capacity for PA promotion.

Physical activity may reduce the risk of developing breast cancer via its effect on the insulin/insulin-like growth factor (IGF) signaling system. A systematic review searched for randomized controlled trials (RCT), Mendelian randomization and prospective cohort studies that examined the effects of physical activity on insulin/IGF signaling [IGFs, their binding proteins (IGFBP), and markers of insulin resistance] in adult women. Meta-analyses were performed to generate effect estimates. Risk of bias was assessed, and the Grading of Recommendations Assessment, Development, and Evaluation system used to determine the overall quality of the evidence. Fifty-eight RCTs met our inclusion criteria, no observational or Mendelian randomization studies met the criteria for inclusion. Meta-analyses indicated that physical activity interventions (vs. control) reduced fasting insulin, the Homeostatic Model Assessment for Insulin Resistance and fasting glucose. Physical activity increased IGF-1, but there was no clear effect on IGFBP-3 or the ratio of IGF-1:IGFBP-3. Strong evidence was only established for fasting insulin and insulin resistance. Further research is needed to examine the effect of physical activity on C-peptide and HBA1c in women. Reductions in fasting insulin and insulin resistance following exercise suggest some biological plausibility of the first part of the physical activity-insulin/IGF signaling-breast cancer pathway. See related article by Drummond et al., p. 2116., (©2022 American Association for Cancer Research.)

Objectives: Physical inactivity and sedentary behaviour are associated with higher breast cancer risk in observational studies, but ascribing causality is difficult. Mendelian randomisation (MR) assesses causality by simulating randomised trial groups using genotype. We assessed whether lifelong physical activity or sedentary time, assessed using genotype, may be causally associated with breast cancer risk overall, pre/post-menopause, and by case-groups defined by tumour characteristics., Methods: We performed two-sample inverse-variance-weighted MR using individual-level Breast Cancer Association Consortium case-control data from 130 957 European-ancestry women (69 838 invasive cases), and published UK Biobank data (n=91 105-377 234). Genetic instruments were single nucleotide polymorphisms (SNPs) associated in UK Biobank with wrist-worn accelerometer-measured overall physical activity (n snps =5) or sedentary time (n snps =6), or accelerometer-measured (n snps =1) or self-reported (n snps =5) vigorous physical activity., Results: Greater genetically-predicted overall activity was associated with lower breast cancer overall risk (OR=0.59; 95% confidence interval (CI) 0.42 to 0.83 per-standard deviation (SD;~8 milligravities acceleration)) and for most case-groups. Genetically-predicted vigorous activity was associated with lower risk of pre/perimenopausal breast cancer (OR=0.62; 95% CI 0.45 to 0.87,≥3 vs. 0 self-reported days/week), with consistent estimates for most case-groups. Greater genetically-predicted sedentary time was associated with higher hormone-receptor-negative tumour risk (OR=1.77; 95% CI 1.07 to 2.92 per-SD (~7% time spent sedentary)), with elevated estimates for most case-groups. Results were robust to sensitivity analyses examining pleiotropy (including weighted-median-MR, MR-Egger)., Conclusion: Our study provides strong evidence that greater overall physical activity, greater vigorous activity, and lower sedentary time are likely to reduce breast cancer risk. More widespread adoption of active lifestyles may reduce the burden from the most common cancer in women., Competing Interests: Competing interests: MWB conducts research funded by Amgen, Novartis and Pfizer. PAF conducts research funded by Amgen, Novartis and Pfizer. He received honoraria from Roche, Novartis and Pfizer. AWK declares research funding to her institution from Myriad Genetics for an unrelated project (funding dates 2017-2019). SL declares grants and honoraria paid to her institution from Amgen, Novartis, Pfizer, Roche, and, outside the submitted work, grants and/or honoraria paid to her institution from AbbVie, Celgene, Seattle Genetics, PrIME/Medscape, Daiichi-Sankyo, Lilly, Samsung, BMS, Puma, Immunomedics, AstraZeneca, Pierre Fabre, Merck, GlaxoSmithKlein, EirGenix, and Bayer, and personal fees from Chugai; SL also has a patent EP14153692.0 pending. UM declares stock ownership in Abcodia Ltd. RAM has been a consultant for Pharmavite. No other authors have conflicts to declare., (© Author(s) (or their employer(s)) 2022. No commercial re-use. See rights and permissions. Published by BMJ.)

Purpose: High-grade disease accounts for ~ 70% of all glioma, and has a high mortality rate. Few modifiable exposures are known to be related to glioma risk or mortality., Methods: We examined associations between lifetime physical activity and physical activity at different ages (15-18 years, 19-29 years, 30-39 years, last 10 years) with the risk of glioma diagnosis, using data from a hospital-based family case-control study (495 cases; 371 controls). We followed up cases over a median of 25 months to examine whether physical activity was associated with all-cause mortality. Physical activity and potential confounders were assessed by self-administered questionnaire. We examined associations between physical activity (metabolic equivalent [MET]-h/wk) and glioma risk using unconditional logistic regression and with all-cause mortality in cases using Cox regression., Results: We noted a reduced risk of glioma for the highest (≥ 47 MET-h/wk) versus lowest (< 24 METh/wk) category of physical activity for lifetime activity (OR = 0.58, 95% CI: 0.38-0.89) and at 15-18 years (OR = 0.57, 95% CI: 0.39-0.83). We did not observe any association between physical activity and all-cause mortality (HR for lifetime physical activity = 0.91, 95% CI: 0.64-1.29)., Conclusion: Our findings are consistent with previous research that suggested physical activity during adolescence might be protective against glioma. Engaging in physical activity during adolescence has many health benefits; this health behavior may also offer protection against glioma., (© 2022. The Author(s).)

Background: Higher levels of time spent sitting (sedentary behavior) contribute to adverse health outcomes, including earlier death. This effect may be modified by other lifestyle factors. We examined the association of television viewing (TV), a common leisure-time sedentary behavior, with all-cause mortality, and whether this is modified by body mass index (BMI), physical activity, smoking, alcohol intake, soft drink consumption, or diet-associated inflammation., Methods: Using data from participants in the Melbourne Collaborative Cohort Study, flexible parametric survival models assessed the time-dependent association of self-reported TV time (three categories: < 2 h/day, 2-3 h/day, > 3 h/day) with all-cause mortality. Interaction terms were fitted to test whether there was effect modification of TV time by the other risk factors., Results: From 19,570 participants, 4,417 deaths were reported over a median follow up of 14.5 years. More TV time was associated with earlier mortality; however, this relationship diminished with increasing age. The hazard ratio (HR) and 95% confidence interval (95% CI) for > 3 h/day compared with < 2 h/day of TV time was 1.34 (1.16, 1.55) at 70 years, 1.14 (1.04, 1.23) at 80 years, and 0.95 (0.84, 1.06) at 90 years. The TV time/mortality relationship was more evident in participants who were physically inactive (compared with active; p for interaction < 0.01) or had a higher dietary inflammatory index score (compared with a lower score; p for interaction = 0.03). No interactions were detected between TV time and BMI, smoking, alcohol intake, nor soft-drink consumption (all p for interaction > 0.16)., Conclusions: The relationship between TV time and all-cause mortality may change with age. It may also be more pronounced in those who are otherwise inactive or who have a pro-inflammatory diet., (© 2022. The Author(s).)

Epidemiologic research suggests that physical activity is associated with a reduced risk of breast cancer, but the causal nature of this link is not clear. Investigating mechanistic pathways can provide evidence of biological plausibility and improve causal inference. This project will examine three putative pathways (sex steroid hormones, insulin signaling, and inflammation) in a series of two-stage systematic reviews. Stage 1 used Text Mining for Mechanism Prioritisation (TeMMPo) to identify and prioritize relevant biological intermediates. Stage 2 will systematically review the findings from studies of (i) physical activity and intermediates and (ii) intermediates and breast cancer. Ovid MEDLINE, EMBASE, and SPORTDiscus will be searched using a combination of subject headings and free-text terms. Human intervention and prospective, observational studies will be eligible for inclusion. Meta-analysis will be performed where possible. Risk of bias will be assessed using the Cochrane Collaboration tool, or the ROBINS-I or ROBINS-E tool, depending on study type. Strength of evidence will be assessed using the GRADE system. In addition to synthesizing the mechanistic evidence that links physical activity with breast cancer risk, this project may also identify priority areas for future research and help inform the design and implementation of physical activity interventions. See related reviews by Swain et al., p. 16 and Drummond et al., p. 28 ., (©2021 The Authors; Published by the American Association for Cancer Research.)

The effect of physical activity on breast cancer risk may be partly mediated by sex steroid hormones. This review synthesized and appraised the evidence for an effect of physical activity on sex steroid hormones. Systematic searches were performed using MEDLINE (Ovid), EMBASE (Ovid), and SPORTDiscus to identify experimental studies and prospective cohort studies that examined physical activity and estrogens, progestins, and/or androgens, as well as sex hormone binding globulin (SHBG) and glucocorticoids in pre- and postmenopausal women. Meta-analyses were performed to generate effect estimates. Risk of bias was assessed, and the GRADE system was used to appraise quality of the evidence. Twenty-eight randomized controlled trials (RCT), 81 nonrandomized interventions, and six observational studies were included. Estrogens, progesterone, and androgens mostly decreased, and SHBG increased, in response to physical activity. Effect sizes were small, and evidence quality was graded moderate or high for each outcome. Reductions in select sex steroid hormones following exercise supports the biological plausibility of the first part of the physical activity-sex hormone-breast cancer pathway. The confirmed effect of physical activity on decreasing circulating sex steroid hormones supports its causal role in preventing breast cancer. See related reviews by Lynch et al., p. 11 and Drummond et al., p. 28 ., (©2021 The Authors; Published by the American Association for Cancer Research.)

Objectives: To estimate the extent of measurement error in the Active Australia questionnaire, and to examine the impact of measurement error on the association of moderate-vigorous physical activity (MVPA) with obesity., Design: Accelerometer Validation Study, cross-sectional; data from the third wave of a prospective cohort (Australian Diabetes, Obesity, and Lifestyle (AusDiab) Study))., Methods: Self-reported physical activity data were obtained from 4005 participants of the third wave of the AusDiab study via the Active Australia questionnaire. Accelerometer-derived physical activity data were obtained from a subsample of 670 participants. Validity coefficients and attenuation factors were estimated from a measurement error model. A regression calibration method was applied to a logistic regression model examining the association between self-reported MVPA and obesity to adjust observed odds ratios (OR) for measurement error., Results: The validity coefficient was 0.35 (0.28, 0.43) and the attenuation factor was 0.16 (0.13, 0.20) in models adjusted for age and sex. The uncorrected OR for obesity for 210min/week of MVPA (50th percentile) relative to 80min/week (25th percentile) was 0.87 (0.85, 0.90). The attenuation factor was used to adjust this OR for measurement error, giving a corrected OR of 0.43 (0.32, 0.55)., Conclusions: Substantial measurement error (relative to accelerometry) was evident in the Active Australia questionnaire, leading to attenuation of the association of MVPA with obesity. A regression-calibration method can be used to adjust risk estimates for associations between self-reported MVPA and health-related outcomes for measurement error specific to self-report. These corrected risk estimates reflect associations that would be expected if MVPA were measured by accelerometry., (Copyright © 2020 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.)

Introduction: Long-term effects of physical activity and television (TV) viewing on mortality have been inferred from observational studies. The associations observed do not allow for inferences about the effects of population interventions and could be subject to bias due to time-varying confounding., Methods: Using data from the Australian Diabetes, Obesity and Lifestyle Study, collected in 1999-2000 (T0), 2004-2005 (T1), and 2011-2012 (T2), we applied the parametric g-formula to estimate cumulative risks of death under hypothetical interventions on physical activity and/or TV viewing determined from self-report while adjusting for time-varying confounding., Results: In the 6377 participants followed up for 13 yr from 2004 to 2005 to death or censoring in 2017, 781 participants died. The observed cumulative risk of death was 12.2%. The most effective hypothetical intervention was to increase weekly physical activity to >300 min (risk ratio (RR), 0.66 (0.46-0.86) compared with a "worst-case" scenario; RR, 0.83 (0.73-0.94) compared with no intervention). Reducing daily TV viewing to <2 h in addition to physical activity interventions did not show added survival benefits. Reducing TV viewing alone was least effective in reducing mortality (RR, 0.85 (0.60-1.10) compared with the worst-case scenario; RR, 1.06 (0.93-1.20) compared with no intervention)., Conclusions: Our findings suggested that sustained interventions to increase physical activity could lower all-cause mortality over a 13-yr period, and there might be limited gain from intervening to reduce TV viewing time in a relatively healthy population., (Copyright © 2020 by the American College of Sports Medicine.)

Purpose: Using the Melbourne Collaborative Cohort Study, we examined the associations of occupation, household, transport, and leisure physical activity with pain interference with normal work and muscle pain after activity., Methods: This cross-sectional analysis included 7655 working and 11,766 nonworking participants. Physical activity was assessed using the long-form International Physical Activity Questionnaire. Pain interference was assessed with the Short-Form 12-Item Health Survey version 2.0, and muscle pain after activity was assessed using the 12-item Somatic and Psychological Health Report. Ordered logistic regression was used to estimate odds ratios (OR) and 95% confidence intervals (CI), and restricted cubic splines were used to graphically represent the shape of associations., Results: All physical activity domain-pain outcome associations were nonlinear. Compared with participants who reported the lowest level of activity, participants who reported the median level of transport physical activity (10 MET·h·wk) reported less pain interference (workers: OR, 0.86 [95% CI, 0.77-0.97]; nonworkers: OR, 0.88 [95% CI, 0.79-0.97]) and muscle pain after activity (workers: OR, 0.81 [95% CI, 0.70-0.95]; nonworkers: OR, 0.86 [95% CI, 0.77-0.95]). Higher levels of leisure time activity (20 MET·h·wk) were associated with less pain interference in nonworkers (OR, 0.87; 95% CI, 0.77-0.98) and muscle pain after activity in workers (OR, 0.67; 95% CI, 0.56-0.80). Workers who reported the median level of household activity (16 MET·h·wk) had increased pain interference (OR, 1.19; 95% CI, 1.07-1.32) and muscle pain after activity (OR, 1.23; 95% CI, 1.06-1.42) than did those who reported the least household activity., Conclusions: Associations between domain-specific physical activity and pain outcomes were not uniform. Within the transport and leisure domains, physical activity was inversely associated with pain-related outcomes, whereas household physical activity was positively associated with pain scores within the working sample.

Background: Prolonged sitting time is a risk factor for chronic disease, yet recent global surveillance is not well described. The aims were to clarify: (i) the countries that have collected country-level data on self-reported sitting time; (ii) the single-item tools used to collect these data; and (iii) the duration of sitting time reported across low- to high-income countries., Methods: Country-level data collected within the last 10 years using single-item self-report were included. The six-stage methodology: (1) reviewing Global Observatory for Physical Activity! Country Cards; (2-4) country-specific searches of PubMed, the Demographic and Health Survey website and Google; (5) analysing the Eurobarometer 88.4; and (6) country-specific searches for World Health Organization STEPwise reports., Results: A total of 7641 records were identified and screened for eligibility. Sixty-two countries (29%) reported sitting time representing 47% of the global adult population. The majority of data were from high-income (61%) and middle income (29%) countries. The tools used were the International Physical Activity Questionnaire (IPAQ; n = 34), a modified IPAQ (n = 1) or the Global Physical Activity Questionnaire (GPAQ; n = 27). The median of mean daily sitting times was 4.7 (IQR: 3.5-5.1) hours across all countries. Higher-income countries recorded a longer duration of sitting time than lower-income countries (4.9 vs 2.7 h)., Conclusions: This study provides an updated collation of countries collecting self-reported sitting time data. The daily sitting time findings should be interpreted cautiously. Current surveillance of sitting time is limited by a lack of coverage. Measures of population sitting time that are valid, feasible and sensitive to change should be embedded within global surveillance systems, to help guide future policy, research and practice., Trial Registration: Not applicable.

Background: Prostate cancer is the second most common male cancer worldwide, but there is substantial geographical variation, suggesting a potential role for modifiable risk factors in prostate carcinogenesis., Methods: We identified previously reported prostate cancer risk factors from the World Cancer Research Fund (WCRF)'s systematic appraisal of the global evidence (2018). We assessed whether each identified risk factor was causally associated with risk of overall (79 148 cases and 61 106 controls) or aggressive (15 167 cases and 58 308 controls) prostate cancer using Mendelian randomization (MR) based on genome-wide association-study summary statistics from the PRACTICAL and GAME-ON/ELLIPSE consortia. We assessed evidence for replication in UK Biobank (7844 prostate-cancer cases and 204 001 controls)., Results: WCRF identified 57 potential risk factors, of which 22 could be instrumented for MR analyses using single nucleotide polymorphisms. For overall prostate cancer, we identified evidence compatible with causality for the following risk factors (odds ratio [OR] per standard deviation increase; 95% confidence interval): accelerometer-measured physical activity, OR = 0.49 (0.33-0.72; P = 0.0003); serum iron, OR = 0.92 (0.86-0.98; P = 0.007); body mass index (BMI), OR = 0.90 (0.84-0.97; P = 0.003); and monounsaturated fat, OR = 1.11 (1.02-1.20; P = 0.02). Findings in our replication analyses in UK Biobank were compatible with our main analyses (albeit with wide confidence intervals). In MR analysis, height was positively associated with aggressive-prostate-cancer risk: OR = 1.07 (1.01-1.15; P = 0.03)., Conclusions: The results for physical activity, serum iron, BMI, monounsaturated fat and height are compatible with causality for prostate cancer. The results suggest that interventions aimed at increasing physical activity may reduce prostate-cancer risk, although interventions to change other risk factors may have negative consequences on other diseases., (© The Author(s) 2019; all rights reserved. Published by Oxford University Press on behalf of the International Epidemiological Association.)

Purpose: To determine whether recommended amounts of leisure-time physical activity (ie, 7.5-15 metabolic equivalent task [MET] hours/week) are associated with lower cancer risk, describe the shape of the dose-response relationship, and explore associations with moderate- and vigorous-intensity physical activity., Methods: Data from 9 prospective cohorts with self-reported leisure-time physical activity and follow-up for cancer incidence were pooled. Multivariable Cox regression was used to estimate adjusted hazard ratios (HRs) and 95% CIs of the relationships between physical activity with incidence of 15 types of cancer. Dose-response relationships were modeled with restricted cubic spline functions that compared 7.5, 15.0, 22.5, and 30.0 MET hours/week to no leisure-time physical activity, and statistically significant associations were determined using tests for trend ( P < .05) and 95% CIs (< 1.0)., Results: A total of 755,459 participants (median age, 62 years [range, 32-91 years]; 53% female) were followed for 10.1 years, and 50,620 incident cancers accrued. Engagement in recommended amounts of activity (7.5-15 MET hours/week) was associated with a statistically significant lower risk of 7 of the 15 cancer types studied, including colon (8%-14% lower risk in men), breast (6%-10% lower risk), endometrial (10%-18% lower risk), kidney (11%-17% lower risk), myeloma (14%-19% lower risk), liver (18%-27% lower risk), and non-Hodgkin lymphoma (11%-18% lower risk in women). The dose response was linear in shape for half of the associations and nonlinear for the others. Results for moderate- and vigorous-intensity leisure-time physical activity were mixed. Adjustment for body mass index eliminated the association with endometrial cancer but had limited effect on other cancer types., Conclusion: Health care providers, fitness professionals, and public health practitioners should encourage adults to adopt and maintain physical activity at recommended levels to lower risks of multiple cancers.

Background: Self-reported physical activity is inaccurate, yet few investigators attempt to adjust for measurement error when estimating risks for health outcomes. We estimated what the association between self-reported physical activity and colorectal cancer risk would be if physical activity had been assessed using accelerometry instead., Methods: We conducted a validation study in which 235 Australian adults completed a telephone-administered International Physical Activity Questionnaire (IPAQ), and wore an accelerometer (Actigraph GT3X+) for 7 days. Using accelerometer-assessed physical activity as the criterion measure, we calculated validity coefficients and attenuation factors using a structural equation model adjusted for age, sex, education and body mass index. We then used a regression calibration approach to apply the attenuation factors to data from the Melbourne Collaborative Cohort Study (MCCS) to compute bias-adjusted hazard ratios (HR) and 95% confidence intervals (CI)., Results: Average daily minutes of physical activity from the short form of the International Physical Activity Questionnaire (IPAQ-short) were substantially higher than accelerometer-measured duration (55 versus 32 min). The validity coefficient (0.32; 95% CI: 0.20, 0.43) and attenuation factor (0.20; 95% CI: 0.12, 0.28) were low. The HRs for colorectal cancer risk for high (75th percentile; 411 min/week) versus low (25th percentile; 62 min/week) levels of self-reported physical activity were 0.95 (95% CI: 0.87, 1.05) before and 0.78 (95% CI: 0.47, 1.28) after bias adjustment., Conclusions: Over-estimation of physical activity by the IPAQ-short substantially attenuates the association between physical activity and colorectal cancer risk, suggesting that the protective effect of physical activity has been previously underestimated., (© The Author(s) 2019; all rights reserved. Published by Oxford University Press on behalf of the International Epidemiological Association.)

Background: The ACTIVATE Trial examined the efficacy of a wearable-based intervention to increase physical activity and reduce sedentary behavior in breast cancer survivors. This paper examines the effects of the intervention on health-related quality of life (HRQoL) and fatigue at 12 weeks (T2; end of intervention) and 24 weeks (T3; follow-up)., Methods: Inactive and postmenopausal women who had completed primary treatment for stage I-III breast cancer were randomized to intervention or waitlist control. Physical activity and sedentary behavior were measured by Actigraph and activPAL accelerometers at baseline (T1), end of the intervention (T2), and 12 weeks follow-up (T3). HRQoL and fatigue were measured using the Functional Assessment of Cancer Therapy-Breast (FACT-B) and the Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-Fatigue). Primary intervention effects were evaluated comparing intervention and waitlist group at T2 using repeated measures mixed effects models., Results: Overall, 83 women were randomized and trial retention was high (94%). A 4.6-point difference in fatigue score was observed between groups at T2 (95% CI: 1.3, 7.8) indicating improvement in fatigue profiles in the intervention group. In within groups analyses, the intervention group reported a 5.1-point increase in fatigue from baseline to T2 (95% CI: 2.0, 8.2) and a 3.3-point increase from baseline to T3 (95% CI: 0.1, 6.41)., Conclusions: Despite small improvements in fatigue profiles, no effects on HRQoL were observed. While the ACTIVATE Trial was associated with improvements in physical activity and sedentary behavior, more intensive or longer duration interventions may be needed to facilitate changes in HRQoL., (© 2019 John Wiley & Sons, Ltd.)

Background: Recent updates to physical activity guidelines highlight the importance of reducing sedentary time. However, at present, only general recommendations are possible (ie, "Sit less, move more"). There remains a need to investigate the strength, temporality, specificity, and dose-response nature of sedentary behavior associations with chronic disease, along with potential underlying mechanisms., Methods: Stemming from a recent research workshop organized by the Sedentary Behavior Council themed "Sedentary behaviour mechanisms-biological and behavioural pathways linking sitting to adverse health outcomes," this paper (1) discusses existing challenges and scientific discussions within this advancing area of science, (2) highlights and discusses emerging areas of interest, and (3) points to potential future directions., Results: A brief knowledge update is provided, reflecting upon current and evolving thinking/discussions, and the rapid accumulation of new evidence linking sedentary behavior to chronic disease. Research "action points" are made at the end of each section-spanning from measurement systems and analytic methods, genetic epidemiology, causal mediation, and experimental studies to biological and behavioral determinants and mechanisms., Conclusion: A better understanding of whether and how sedentary behavior is causally related to chronic disease will allow for more meaningful conclusions in the future and assist in refining clinical and public health policies/recommendations.

Background: It is not always clear whether physical activity is causally related to health outcomes, or whether the associations are induced through confounding or other biases. Randomized controlled trials of physical activity are not feasible when outcomes of interest are rare or develop over many years. Thus, we need methods to improve causal inference in observational physical activity studies., Methods: We outline a range of approaches that can improve causal inference in observational physical activity research, and also discuss the impact of measurement error on results and methods to minimize this., Results: Key concepts and methods described include directed acyclic graphs, quantitative bias analysis, Mendelian randomization, and potential outcomes approaches which include propensity scores, g methods, and causal mediation., Conclusions: We provide a brief overview of some contemporary epidemiological methods that are beginning to be used in physical activity research. Adoption of these methods will help build a stronger body of evidence for the health benefits of physical activity.

Background: There are significant geographic inequalities in cancer survival with poorer survival rates in non-metropolitan areas compared to major cities. Physical activity (PA) can reduce cancer recurrence and prevent cardiovascular disease. However, few survivors participate in sufficient PA and the prevalence of inactivity is significantly higher in non-metropolitan survivors. The study investigated non-metropolitan survivors' recollections regarding PA advice received following cessation of active treatment, their knowledge of PA guidelines, and the factors that impact on PA behaviour change., Method: Sixteen individuals (14 women and 2 men) with breast (n = 8), endometrial (n = 4) or colorectal cancer (n = 4), with a mean age of 60 years (SD = 12) completed semi-structured interviews as part of a larger study to examine the acceptability and utility of wearable trackers to increase PA. Interviews explored survivors' recollections regarding the advice they received concerning PA following active treatment, knowledge of PA guidelines for cancer survivors and the influences on PA behaviour change. Interview transcripts were analysed using thematic analysis., Results: Four main themes emerged: (i) insufficient knowledge of guidelines, (ii) support from the treating oncology team, (iii) external accountability, and (iv) barriers to PA., Conclusions: Survivors' knowledge of PA guidelines was limited and they did not often recall their oncologists making specific recommendations concerning PA. Survivors' referred to the desire for accountability and monitoring in order to successfully change PA. Lack of motivation was the main barrier to PA participation. Other barriers included age, health status, and lack of facilities or exercise programs.

Background: Physical activity has beneficial effects on the health of cancer survivors. We aimed to investigate accelerometer-assessed physical activity and sedentary time in cancer survivors, and describe activity profiles. Additionally, we identify demographic and clinical correlates of physical activity, sedentary time and activity profiles., Methods: Accelerometer, questionnaire and clinical data from eight studies conducted in four countries (n = 1447) were pooled. We calculated sedentary time and time spent in physical activity at various intensities using Freedson cut-points. We used latent profile analysis to identify activity profiles, and multilevel linear regression analyses to identify demographic and clinical variables associated with accelerometer-assessed moderate to vigorous physical activity (MVPA), sedentary time, the highly active and highly sedentary profile, adjusting for confounders identified using a directed acyclic graph., Results: Participants spent on average 26 min (3%) in MVPA and 568 min (66%) sedentary per day. We identified six activity profiles. Older participants, smokers and participants with obesity had significantly lower MVPA and higher sedentary time. Furthermore, men had significantly higher MVPA and sedentary time than women and participants who reported less fatigue had higher MVPA time. The highly active profile included survivors with high education level and normal body mass index. Haematological cancer survivors were less likely to have a highly active profile compared to breast cancer survivors. The highly sedentary profile included older participants, males, participants who were not married, obese, smokers, and those < 12 months after diagnosis., Conclusions: Cancer survivors engage in few minutes of MVPA and spend a large proportion of their day sedentary. Correlates of MVPA, sedentary time and activity profiles can be used to identify cancer survivors at risk for a sedentary and inactive lifestyle.

Background: This brief report examines the maintenance of moderate to vigorous physical activity (MVPA) and sedentary behavior changes approximately 12 weeks after the delivery of the ACTIVATE Trial primary intervention (use of the Garmin Vivofit 2 activity tracker coupled with a behavioral feedback and goal-setting session and 5 telephone-delivered health coaching sessions). We also examine the efficacy of an abridged intervention (use of the Garmin Vivofit 2 only) in the waitlist control group., Methods: A pre-post design was employed to examine the secondary aims of the ACTIVATE Trial (n = 80; mean age = 62 years). MVPA and sedentary behavior were measured using Actigraph and activPAL accelerometers after delivery of the primary intervention (T2), and again 12 weeks later (T3). Linear mixed models with random effects were used to examine within-group changes in MVPA and sitting time variables., Results: After the 12-week follow-up period, women in the primary intervention group had maintained their higher levels of MVPA (change from T2 to T3 = 14 min/wk; 95% CI = -18 to 46; P = .37). However, their sitting time increased slightly, by 7 min/d (95% CI = -20 to 34; P = .58), but it did not return to its preintervention level. After receiving the Garmin Vivofit 2, the waitlist control group increased their MVPA by 33 min/wk (95% CI = 3-64; P = .03) and reduced their sitting time by 38 min/d (95% CI = -69 to -7; P = .02) over the same 12-week period., Conclusion: The secondary outcomes from the ACTIVATE Trial suggest that wearable technology may generate sustainable changes in MVPA and sitting time. Wearable technology alone may be sufficient to change behavior, at least in the short term., (© 2019 American Cancer Society.)

Background: The benefits of an active lifestyle after a breast cancer diagnosis are well recognized, but the majority of survivors are insufficiently active. The ACTIVATE Trial examined the efficacy of an intervention (use of the Garmin Vivofit 2 activity monitor coupled with a behavioral feedback and goal-setting session and 5 telephone-delivered health coaching sessions) to increase moderate to vigorous physical activity (MVPA) and reduce sedentary behavior in breast cancer survivors., Methods: This randomized controlled trial recruited 83 inactive, postmenopausal women diagnosed with stage I-III breast cancer who had completed primary treatment. Participants were randomly assigned to the intervention group or to the control group, and the intervention was delivered over a 12-week period. MVPA and sedentary behavior were measured with Actigraph and activPAL accelerometers at baseline (T1) and at the end of the intervention (T2)., Results: Retention in the trial was high, with 80 (96%) of participants completing T2 data collection. At T2, there was a significant between-group difference in MVPA (69 min/wk; 95% CI = 22-116) favoring the intervention group. The trial resulted in a statistically significant decrease in both total sitting time and prolonged bouts (≥20 min) of sitting, with between-group reductions of 37 min/d (95% CI = -72 to -2) and 42 min/d (95% CI = -83 to -2), respectively, favoring the intervention group., Conclusion: Results from the ACTIVATE Trial suggest that the use of wearable technology presents an inexpensive and scalable opportunity to facilitate more active lifestyles for cancer survivors. Whether or not such wearable technology-based interventions can create sustainable behavioral change should be the subject of future research., (© 2019 American Cancer Society.)

Introduction: Physical activity may affect health via DNA methylation. The epigenetic influences of sedentary behaviors such as television viewing are unknown. We performed a genomewide study of DNA methylation in peripheral blood in relation to physical activity and television viewing time., Methods: DNA methylation was measured using the Illumina Infinium HumanMethylation450K BeadChip array in blood samples collected at baseline (N = 5513) and follow-up (N = 1249) from participants in the Melbourne Collaborative Cohort Study. At baseline, times per week of leisure-time physical activity were self-reported. At follow-up, the International Physical Activity Questionnaire was used to assess MET-hours per week of total and leisure-time physical activity and hours per day of television viewing time. Linear mixed models were used to assess associations between physical activity and television viewing measures and DNA methylation at individual CpG sites, adjusted for potential confounders and batch effects., Results: At follow-up, total physical activity was associated with DNA methylation at cg10266336 (P = 6.0 × 10), annotated to the SAA2 gene. Weaker evidence of associations (P < 1.0 × 10) were observed for an additional 14 CpG sites with total physical activity, for 7 CpG sites with leisure-time physical activity, and for 9 CpG sites with television viewing time. Changes in leisure-time physical activity between baseline and follow-up were associated with methylation changes (P < 0.05) at four of the seven CpG sites with weaker evidence of cross-sectional associations with leisure-time physical activity., Conclusion: Physical activity and television viewing may be associated with blood DNA methylation, a potential pathway to chronic disease development. Further research using accelerometer data and larger sample sizes is warranted.

Background: Physical activity reduces the risk of colorectal cancer (CRC), but the relevant evidence derives primarily from self-reported recreational and occupational activity. Less is known about the contribution of other domains of physical activity, such as transport and household. We examined associations between domain-specific physical activities and CRC risk within the Melbourne Collaborative Cohort Study., Methods: Analyses included 23,586 participants who were free from invasive colorectal cancer and had completed the International Physical Activity Questionnaire-Long Form at follow-up 2 (2003-2007). Cox regression, with age as the time metric, was used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for ordinal categories of each physical activity domain., Results: Adjusted HRs for the highest versus the lowest categories of physical activity were 0.71 (95% CI: 0.51-0.98; p trend  = 0.03) for recreational activity; 0.80 (95% CI: 0.49-1.28; p trend  = 0.38) for occupational activity; 0.90 (95% CI: 0.68-1.19; p trend  = 0.20) for transport activity; and 1.07 (95% CI: 0.82-1.40; p trend  = 0.46) for household activity., Conclusions: Recreational activity was associated with reduced CRC risk. A non-significant, inverse association was observed for occupational activity, whereas no association was found for transport or household domains.

Background: In the cancer survivorship context, physical activity and sedentary behavior have been measured using different methods., Purpose: To conduct a narrative review of published research in cancer survivor populations to summarize the quality and identify gaps in reporting on accelerometer data collection, data processing, and outcome measures in cancer survivors., Methods: An initial PubMed® search of articles published in English was conducted in January 2017, and a final search was conducted in May 2017. Variables extracted included study characteristics, methods for accelerometry data collection (e.g., device used), data processing (e.g., cut points used), and data reporting (e.g., time spent in different activity intensities)., Results: A total of 46 articles were eligible for inclusion in the review. The majority of studies (34 of 46) targeted a single cancer group and 18 of these 34 studies were in survivors of breast cancer. Half (54%) of the studies used an ActiGraph® accelerometer. Methods of accelerometer data processing varied across studies. Definitions of non-wear time, vectors used during processing, and filters applied during processing were reported by 51%, 60%, and 8% of studies, respectively. Most studies reported moderate and vigorous physical activity (78%), 50% reported sedentary time, and 43% reported light-intensity activity. Cut points to categorize these activities varied between studies., Conclusions: This narrative review highlights inconsistency in the methods used to collect, process, and report accelerometry data across cancer survivor studies. Accelerometry has potential to add detailed knowledge of the levels and patterns of physical activities and sedentary behaviors across the cancer spectrum. Recommendations are made to improve data processing and reporting methods to maximize the scientific validity of future accelerometer research in this field.

Background: Physical activity (PA) has been associated with lower risks of several cancers. We examined the association between total and domain-specific PA and risk of all and site-specific cancer risk. Methods: We analyzed baseline data from Alberta's Tomorrow Project. Specifically, adults ages 35-69 years who completed the Past Year Total Physical Activity Questionnaire were included ( n = 26,538). For each activity, participants reported the type, duration, and intensity of PA. Total, recreational, and occupational PA metabolic equivalent hours/week were divided into quartiles. Incident cancer cases up to December 2016 were identified via linkage to the Alberta Cancer Registry. The associations of PA on cancer risk were examined using Cox proportional hazards models. Results: A total of 2,186 participants (8.24%) developed cancer during follow-up from 2001 to 2016. We observed a significant inverse association between total PA and all-cancer incidence in the multivariate-adjusted model [HR Q4vQ1 = 0.87; 95% confidence interval (CI): 0.76-0.99] that remained significant in the latency multivariate-adjusted model. Higher recreational PA was associated with a risk decrease for all-cancer in the latency multivariate-adjusted model (HR = 0.84; 95% CI: 0.74-0.96), and showed a linear inverse association with breast cancer. While none of the HR estimates for quartiles of occupational PA and all-cancer reached statistical significance, the model P trend was marginally significant in the latency multivariate-adjusted model ( P = 0.06). Conclusions: In this cohort of Albertans, higher total PA and recreational PA appears to convey modest protection against the development of all-cancer. Impact: Public health and cancer prevention efforts should focus on encouraging population-level increases in PA. Cancer Epidemiol Biomarkers Prev; 27(8); 945-54. ©2018 AACR ., (©2018 American Association for Cancer Research.)

Background: Physical activity has emerged as an important lifestyle factor for primary prevention of numerous diseases, including postmenopausal breast cancer. No study to date has assessed the acute and long-term effects of year-long aerobic exercise programs differing in prescribed exercise volume on physical activity and sedentary time in postmenopausal women. Therefore, we aimed to examine the effects of two moderate-vigorous intensity exercise doses on total, light and moderate-vigorous intensity physical activity times, and sedentary time in postmenopausal women during the year-long intervention and one year later., Methods: The Breast Cancer and Exercise Trial in Alberta (BETA) was a two-center, two-arm, 12-month randomized controlled trial that included 400 previously inactive postmenopausal women randomized to either 150 (MODERATE) or 300 (HIGH) minutes/week of aerobic exercise. Physical activity and sedentary time were assessed at baseline, 6- (intervention mid-point), 12- (prior to end of intervention) and 24-months (follow-up) with waist-mounted accelerometers (Actigraph GTX3®). Self-reported activity and sedentary time at baseline, 12- and 24-months was also assessed (Past Year Total Physical Activity Questionnaire and SIT-Q). Intention-to-treat analyses were conducted using linear mixed models and adjusted for baseline variables., Results: Both physical activity interventions led to increases in objective and subjective measures of total and moderate-vigorous intensity/recreational physical activity time, coupled with decreases in sedentary time, at 6- and 12-months compared to baseline. Additionally, greater increases in accelerometry-derived total physical activity time at 6- and 12-months, and self-reported recreational activity time at 12-months, compared to baseline were noted in the HIGH versus MODERATE groups. Decreases in total, light and moderate-vigorous intensity physical activity time, and an increase in sedentary time, in both groups were noted at 24-months compared to 12-months. A decrease in light intensity physical activity time in both groups at 24-months compared to baseline was also noted., Conclusion: These findings have important health implications, suggesting that total physical activity time can be increased with greater volumes of prescribed exercise, but that additional support and resources could be used to promote the maintenance of these high levels of aerobic exercise participation following study completion., Trial Registration: clinicaltrials.gov identifier: NCT01435005 (BETA Trial). Registred September 15th 2011 (retrospectively registered).

The influence of lifestyle factors on survival following a diagnosis of colorectal cancer (CRC) is not well established. We examined associations between lifestyle factors measured before diagnosis and CRC survival. The Melbourne Collaborative Cohort Study collected data on alcohol intake, cigarette smoking and physical activity, and body measurements at baseline (1990-1994) and wave 2 (2003-2007). We included participants diagnosed to 31 August 2015 with incident stages I-III CRC within 10-years post exposure assessment. Information on tumor characteristics and vital status was obtained. Tumor DNA was tested for microsatellite instability (MSI) and somatic mutations in oncogenes BRAF (V600E) and KRAS. We estimated hazard ratios (HRs) for associations between lifestyle factors and overall and CRC-specific mortality using Cox regression. Of 724 eligible CRC cases, 339 died (170 from CRC) during follow-up (average 9.0 years). Exercise (non-occupational/leisure-time) was associated with higher CRC-specific survival for stage II (HR = 0.25, 95% CI: 0.10-0.60) but not stages I/III disease (p for interaction = 0.01), and possibly for colon and KRAS wild-type tumors. Waist circumference was inversely associated with CRC-specific survival (HR = 1.25 per 10 cm increment, 95% CI: 1.08-1.44), independent of stage, anatomic site and tumor molecular status. Cigarette smoking was associated with lower overall survival, with suggestive evidence of worse survival for BRAF mutated CRC, but not with CRC-specific survival. Alcohol intake was not associated with survival. Survival did not differ by MSI status. We have identified pre-diagnostic predictors of survival following CRC that may have clinical and public health relevance., (© 2017 UICC.)

Background: Physical activity is positively associated with survival and quality of life among breast cancer survivors. Despite these benefits, the majority of breast cancer survivors are insufficiently active. The potential health benefits of reducing sedentary behaviour (sitting time) in this population have not been extensively investigated. The ACTIVATE Trial will evaluate the efficacy of an intervention that combines wearable technology (the Garmin Vivofit2®) with traditional behavioural change approaches to increase physical activity and reduce sedentary behaviour performed by breast cancer survivors., Methods/design: This randomised controlled trial includes inactive, postmenopausal women diagnosed with stage I-III breast cancer who have completed their primary treatment. Participants are randomly assigned to the primary intervention group (Garmin Vivofit2®; behavioural feedback and goal setting session; and, five telephone-delivered health coaching sessions) or to the wait-list control group. The primary intervention is delivered over a 12-week period. The second 12-week period comprises a maintenance phase for the primary intervention group, and an abridged intervention (Garmin Vivofit2® only) for the wait-list control group. Moderate- to vigorous-intensity physical activity (MVPA) and sedentary behaviour are assessed by accelerometry at baseline (T1), end of intervention (T2), and end of maintenance phase (T3)., Discussion: The ACTIVATE Trial is one of the first studies to incorporate wearable technology into an intervention for cancer survivors. If the use of wearable technology (in combination with behaviour change strategies, or alone) proves efficacious, it may become an inexpensive and sustainable addition to the health promotion strategies available to health care providers in the cancer survivorship context., Trial Registration: ACTRN12616000175471., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Background: Physical activity is associated with reduced risk of colorectal cancer, but most epidemiological studies have focused on occupational and recreational physical activity. The evidence for other domains of activity, and for sedentary behaviour, is limited., Methods: Medline, Embase and Web of Science were searched from inception to December 2015 for studies examining domain-specific physical activity or sedentary behaviour and the risk of colon and/or rectal cancer. We extracted maximally adjusted relative risks (RRs) except when RRs not adjusted for body mass index, were also presented. We used random-effects meta-analysis to compute pooled RRs comparing the highest versus the lowest level of exposure. We used meta-regression to assess sources of heterogeneity in estimates., Results: We identified 17 cohort and 21 case-control studies, of which 17 had occupational data, 23 had recreational data, three each had data on transport and household physical activity domains, and 6 studies had data on occupational sedentary behaviour. The pooled relative risks (RRs) for colon cancer were 0.74 (95% confidence interval (CI): 0.67, 0.82) for occupational activity, 0.80 (95% CI: 0.71, 0.89) for recreational activity, 0.66 (95% CI: 0.45, 0.98) for transport-related physical activity, 0.85 (95% CI: 0.71, 1.02) for household physical activity, and 1.44 (95% CI: 1.28, 1.62) for occupational sedentary behaviour. For rectal cancer, the pooled RRs were 0.88 (95% CI: 0.79, 0.98) for occupational activity, 0.87 (95% CI: 0.75, 1.01) for recreational activity, 0.88 (95% CI: 0.70, 1.12) for transport-related physical activity, 1.01 (95% CI: 0.80, 1.27) for household physical activity, and 1.02 (95% CI: 0.82, 1.28) for occupational sedentary behaviour., Conclusions: In addition to increasing occupational and recreational physical activity, promoting physical activity during transport and reducing sedentary behaviour in the workplace may also be useful colorectal cancer prevention strategies., (© The Author 2017; all rights reserved. Published by Oxford University Press on behalf of the International Epidemiological Association)

Background: Physical inactivity and sedentary behaviour are common amongst breast cancer survivors. These behaviours are associated with an increased risk of comorbidities such as heart disease, diabetes and other cancers. Commercially available, wearable activity trackers (WATs) have potential utility as behavioural interventions to increase physical activity and reduce sedentary behaviour within this population., Purpose: The purpose of the study is to explore the acceptability and usability of consumer WAT amongst postmenopausal breast cancer survivors., Methods: Fourteen participants tested two to three randomly assigned trackers from six available models (Fitbit One, Jawbone Up 24, Garmin Vivofit 2, Garmin Vivosmart, Garmin Vivoactive and Polar A300). Participants wore each device for 2 weeks, followed by a 1-week washout period before wearing the next device. Four focus groups employing a semi-structured interview guide explored user perceptions and experiences. We used a thematic analysis approach to analyse focus group transcripts., Results: Five themes emerged from our data: (1) trackers' increased self-awareness and motivation, (2) breast cancer survivors' confidence and comfort with wearable technology, (3) preferred and disliked features of WAT, (4) concerns related to the disease and (5) peer support and doctor monitoring were possible strategies for WAT application., Conclusions: WATs are perceived as useful and acceptable interventions by postmenopausal breast cancer survivors. Effective WAT interventions may benefit from taking advantage of the simple features of the trackers paired with other behavioural change techniques, such as specialist counselling, doctor monitoring and peer support, along with simple manual instructions.

The purpose of this study was to examine potential effects of reallocating time between sleep, sedentary and active behaviours on fatigue symptoms and quality of life in a sample of non-Hodgkin lymphoma survivors. Non-Hodgkin lymphoma survivors identified from the Western Australian Cancer Registry (N = 149) (response rate = 36%; median age = 64 years) wore an Actigraph® GT3X+ accelerometer for 7 days and completed the Fatigue Scale, the Functional Assessment of Cancer Therapy-General and the Pittsburgh Sleep Quality Index. We used isotemporal substitution methods in linear regression models to examine the potential effects of reallocating time between sleep, sedentary and activity behaviours on fatigue and quality of life. Data collection was conducted in Western Australia in 2013. Significant differences were observed for fatigue symptoms when 30 min per day of bouted moderate-to-vigorous physical activity (10 min) was reallocated from 30 min per day of sleep (5.7 points, 95% CI = 1.8, 9.7), sedentary time bouts (20 min) (5.7 points, 95% CI = 1.6, 9.7), sedentary time non-bouts (5.1 points, 95% CI = 1.0, 9.3) or light intensity activity (5.5 points, 95% CI = 1.5, 9.5). Isotemporal substitution effects of reallocating sedentary time, sleep and light physical activity with bouted physical activity was significantly associated with fatigue, but not quality of life. Findings from the present study may aid in the development and delivery of health behaviour interventions that are more likely to influence the health outcome of interest.

Background: The Stand Up Victoria multi-component intervention successfully reduced workplace sitting time in both the short (three months) and long (12 months) term. To further understand how this intervention worked, we aimed to assess the impact of the intervention on four social-cognitive constructs, and examined whether these constructs mediated intervention effects on workplace sitting time at 3 and 12 months post-baseline., Methods: Two hundred and thirty one office-based workers (14 worksites, single government employer) were randomised to intervention or control conditions by worksite. The intervention comprised organisational, environmental, and individual level elements. Participant characteristics and social-cognitive constructs (perceived behavioural control, barrier self-efficacy, perceived organisational norms and knowledge) were measured through a self-administered online survey at baseline, 3 months and 12 months. Workplace sitting time (min/8 h day) was measured with the activPAL3 device. Single multi-level mediation models were performed for each construct at both time points., Results: There were significant intervention effects at 3 months on perceived behavioural control, barrier self-efficacy and perceived organisational norms. Effects on perceived organisational norms were not significant at 12 months. Perceived behavioural control significantly mediated intervention effects at 3 months, accounting for a small portion of the total effect (indirect effect: -8.6 min/8 h day, 95% CI: -18.5, -3.6 min; 7.5% of total effect). At 12 months, barrier self-efficacy significantly mediated the intervention effects on workplace sitting time (indirect effect: -10.3 min/8 h day, 95% CI: -27.3, -2.2; 13.9% of total effect). No significant effects were observed for knowledge at either time point., Conclusions: Strategies that aim to increase workers' perceived control and self-efficacy over their sitting time may be helpful components of sedentary behaviour interventions in the workplace. However, social-cognitive factors only partially explain variation in workplace sitting reduction. Understanding the importance of other levels of influence (particularly interpersonal and environmental) for initiating and maintaining workplace sedentary behaviour change will be informative for intervention development and refinement., Trial Registration: This study was prospectively registered with the Australian New Zealand Clinical Trials register ( ACTRN12611000742976 ) on 15 July 2011.

Objective: To assess differences in accelerometer-assessed moderate- to vigorous-intensity physical activity (MVPA), light-intensity physical activity, and sedentary time between cancer survivors and adults without cancer., Patients and Methods: Accelerometer data collected from 241 breast cancer survivors (ACCEL-Breast study, 2013) and 171 colon cancer survivors (ACCEL-Colon study, 2012-2013) were pooled with data collected from adults without cancer (Australian Diabetes, Obesity and Lifestyle accelerometer substudy, 2011-2012). Linear regression was used to estimate differences in physical activity and sedentary behavior levels between cancer survivors and adults without cancer, adjusted for potential confounding factors., Results: The mean MVPA was significantly higher among breast cancer survivors than among females who had not had cancer (29 vs 22 min/d; P<.001). Colon cancer survivors had significantly lower levels of light activity than did adults without cancer (311 vs 338 min/d; P<.001), more sedentary time (532 vs 507 min/d; P=.003), and more prolonged sedentary time (210 vs 184 min/d; P=.002)., Conclusion: Contrary to findings from previous research (based on self-reported physical activity), cancer survivors engaged in more (breast) or equivalent (colon) MVPA compared with adults without cancer. Differences between colon cancer survivors and adults without cancer for light activity and sedentary behavior highlight the importance of considering the full activity spectrum in the context of cancer control., (Copyright © 2017 Mayo Foundation for Medical Education and Research. Published by Elsevier Inc. All rights reserved.)

Objectives: Few studies have measured the physical activity levels of non-Hodgkin lymphoma (NHL) survivors, and no previous studies have measured sedentary behavior levels in this population. This study used accelerometers to measure the physical activity and sedentary time levels of NHL survivors and examined the demographic, behavioral, and medical correlates of these behaviors., Methods: A total of 156 NHL survivors (mean age = 64 years) completed a questionnaire and wore an accelerometer for seven consecutive days during waking hours. Descriptive statistics were used to describe physical activity and sedentary time levels, and linear regression was used to investigate correlates of these behaviors., Results: Participants averaged 8.6 h of sedentary time per day (60% of their accelerometer wear time), 5.3 h of light-intensity physical activity (37%), and 30 min of moderate-intensity physical activity (3%). Only 12% of the participants accrued the duration of moderate-vigorous physical activity recommended by physical activity guidelines (30 min accrued in bouts of at least 10 min). Female participants, older participants, smokers, and participants with larger waist circumference had lower levels of moderate-to-vigorous intensity physical activity. Smokers and participants with larger waist circumference also had higher sedentary time levels., Conclusion: The NHL survivors in this study spent the majority of their waking hours sedentary, and few met physical activity guidelines. The results of this study emphasize the need for more research exploring the health consequences of sedentary behavior and physical inactivity in NHL survivors. Copyright © 2015 John Wiley & Sons, Ltd., (Copyright © 2015 John Wiley & Sons, Ltd.)

Background: Moderate-to-vigorous intensity physical activity (MVPA) is inversely associated with waist circumference and body mass index (BMI) among breast cancer survivors. Limited research has focused on behaviors that account for larger portions of the day [sleep, sedentary time, and light-intensity physical activity (LPA)]. We investigated the interdependent associations of self-reported sleep, objectively assessed prolonged and short bouts of sedentary time, total LPA, and total MVPA with waist circumference and BMI., Methods: A cross-sectional sample of breast cancer survivors (N = 256, mean age = 60 years; mean time since diagnosis = 3 years) wore an Actigraph GT3X+ accelerometer during waking hours for 7 days. Participants completed the Pittsburgh Sleep Quality Index and self-reported their waist circumference, height, and weight. An isotemporal substitution approach was used in linear regression models to explore the associations of reallocating time to sleep, sedentary and active behaviors on waist circumference, and BMI, after adjusting for potential confounders., Results: Reallocating 30 minutes to MVPA was significantly associated with lower waist circumference when allocated from sleep (-2.50 cm), prolonged sedentary time (-2.51 cm), or LPA (-2.71 cm). Reallocating 30 minutes of prolonged sedentary time to nonprolonged sedentary time was significantly associated with lower waist circumference (-0.94 cm). Similar results were observed for BMI., Conclusions: Reallocating 30 minutes to MVPA was associated with significantly lower waist circumference and BMI, as was reallocating 30 minutes of prolonged sedentary time to 30 minutes of nonprolonged sedentary time., Impact: Increasing MVPA levels and decreasing time spent in prolonged, unbroken sedentary bouts may be avenues for improving body composition in this population. Cancer Epidemiol Biomarkers Prev; 26(2); 254-60. ©2016 AACR., Competing Interests: None to declare, (©2016 American Association for Cancer Research.)

Background: Recent evidence links sedentary behaviour (or too much sitting) with poorer health outcomes; many adults accumulate the majority of their daily sitting time through occupational sitting and TV viewing. To further the development and targeting of evidence-based strategies there is a need for identification of the factors associated with higher levels of these behaviours. This study examined socio-demographic and health-related correlates of occupational sitting and of combined high levels of occupational sitting/TV viewing time amongst working adults., Methods: Participants were attendees of the third wave (2011/12) of the Australian Diabetes, Obesity and Lifestyle (AusDiab) study who worked full-time (≥35 h/week; n = 1,235; 38 % women; mean ± SD age 53 ± 7 years). Logistic and multinomial logistic regression analyses were conducted (separately for women and men) to assess cross-sectional associations of self-reported occupational sitting time (categorised as high/low based on the median) and also the combination of occupational sitting time/TV viewing time (high/low for each outcome), with a number of potential socio-demographic and health-related correlates., Results: Higher levels of occupational sitting (>6 h/day) were associated with higher household income for both genders. Lower levels of occupational sitting were associated with being older (women only); and, for men only, having a blue collar occupation, having a technical/vocational educational attainment, and undertaking more leisure-time physical activity (LTPA). Attributes associated with high levels of both occupational sitting and TV viewing time included white collar occupation (men only), lower levels of LTPA (both genders), higher BMI (men), and higher energy consumption (women)., Conclusions: Higher household income (both genders) and professional/managerial occupations (men only) were correlates of high occupational sitting time, relative to low occupational sitting time, while health-related factors (lower LTPA, higher BMI - men, and higher energy consumption - women) were associated with high levels of both occupational sitting and TV viewing time, relative to low occupational sitting and low TV viewing time. These findings suggest possible high-risk groups that may benefit from targeted interventions. Further research is needed on potentially modifiable environmental and social correlates of occupational sitting time, in order to inform workplace initiatives.

Purpose: The purpose of this study was to determine associations of objectively assessed moderate-to-vigorous intensity physical activity (MVPA) and sedentary time with psychological health outcomes including depression symptoms, anxiety symptoms, and overall satisfaction with life in colon cancer survivors., Methods: Colon cancer survivors (N = 180) from Alberta, Canada (n = 91), and Western Australia (n = 89) completed a mailed survey that assessed depression symptom severity, state anxiety, and satisfaction with life (SWL). Sedentary time and MVPA were assessed using the Actigraph(®) GT3X+ accelerometer (60-s epochs) via a 7-day monitoring protocol. MVPA and sedentary time were corrected for wear time and then examined as quartiles (Q). Multivariate analysis of variance was used to examine associations of MVPA and sedentary time with psychological health., Results: There was a significant association between psychological health outcomes and objectively assessed MVPA [Wilks' λ = 0.886, F(3382.2) = 2.156, p = 0.024] that suggested a small and significant association between MVPA and SWL (p = 0.032). A significant multivariate analysis of variance (MANOVA) [Wilks' λ = 0.945, F(3159) = 3.1, p = 0.028] suggested participants meeting guidelines reported significantly fewer anxiety symptoms (M(diff) = -1.23, p = 0.027) and higher perceptions of SWL (M(diff) = 3.0, p = 0.008). No significant associations emerged for sedentary time [Wilks' λ = 0.956, F(9382.3) = 0.788, p = 0.628]., Conclusions: Contrary to previously published research using self-reports, objectively assessed MVPA and sedentary time were not associated with depression symptoms. Objectively assessed MVPA was associated with SWL and anxiety outcomes in colon cancer survivors., Implications for Cancer Survivors: Colon cancer survivors should continue to engage in regular and sustained MVPA for the accrual of psychological health benefits.

Purpose: Research conducted on the general population indicates self-reported measures of physical activity and sedentary behaviour are inaccurate when compared with objective measures; however, it is not clear if this also applies to cancer survivors. In this study, we compared accelerometer-based and self-reported measures of moderate- to vigorous-intensity physical activity (MVPA) and sedentary time among colon cancer survivors., Methods: A total of 176 colon cancer survivors, recruited from the Western Australia and Alberta cancer registries, wore an Actigraph GT3X+ accelerometer for 7 days and completed self-reported questions about recent MVPA (Godin Leisure-Time Exercise Questionnaire) and usual sedentary time (Marshall Domain-Specific Sitting Questionnaire). Accelerometer data were processed using 60-s epochs and summarized using Freedson's cut points. Spearman's rho and intraclass correlation coefficients (ICCs) were used to assess correlation and agreement for daily MVPA and sedentary time estimates from the two methods., Results: Total mean minutes per day spent in MVPA was 12 min based on accelerometer data and 26 min based on self-reported data (P Difference  < 0.01). Correlation between the methods was fair (rho = 0.51); however, agreement was poor (ICC = 0.33). Mean daily time spent sedentary was similar in both methods (∼8.5 h); however, both correlation and agreement were poor (rho = 0.19, ICC = 0.16)., Conclusions: We found fair correlation but poor agreement between the self-reported and accelerometer-based assessments of MVPA used in this study. For sedentary time, both correlation and agreement between the two methods were poor. Studies of colon cancer survivors using these self-report measures are likely to have a considerable amount of exposure misclassification.

Background: Exercise has favorable effects on biomarkers associated with a lower risk of breast cancer, however it is unclear if higher doses of exercise provide additional effects. No clinical trial has systematically examined how different exercise volumes influence the mechanisms underlying breast cancer etiology. The Breast Cancer and Exercise Trial in Alberta (BETA) - a follow-up study to the Alberta Physical Activity and Breast Cancer Prevention (ALPHA) Trial - is examining how a one-year, high versus moderate volume aerobic exercise intervention influences several biomechanisms hypothesized to influence breast cancer risk in a group of postmenopausal women. Secondary aims are to compare intervention effects on psychosocial and quality of life outcomes as well as understand exercise adherence at 12 and 24 months, and maintenance of all study outcomes at 24 months., Methods/design: The BETA Trial is a two-center, two-armed randomized controlled exercise intervention trial conducted in 400 previously inactive, postmenopausal women aged 50-74 years, in Alberta, Canada. Participants were randomly assigned to a one-year aerobic exercise intervention of either high volume (300 minutes/week) or moderate volume (150 minutes/week). Blood draws and accelerometry were performed at baseline, six and 12 months. Baseline and 12-month measurements were taken of adiposity (including dual energy X-ray absorptiometry and computed tomography scans), physical fitness, dietary intake, self-reported physical activity and sedentary behavior, quality of life, perceived stress, happiness, sleep, and determinants of exercise adherence. Exercise maintenance was assessed and all study measurements were repeated at 24 months. Blood will be analyzed for endogenous estrogens, insulin resistance indicators, and inflammatory markers., Discussion: The BETA Trial will compare the impact of a high versus moderate volume of aerobic exercise on a variety of biological, physiological, and psychological outcomes of relevance to postmenopausal women. A tightly controlled exercise intervention and objective outcome measurements are methodological strengths. The BETA Trial will inform future prevention initiatives by assessing adherence to a high volume of exercise over 12 months by postmenopausal women, and the ability of these women to maintain activity over the longer-term. The ultimate objective is to inform public health guidelines for reducing breast cancer risk through physical activity., Clinical Trials Registration Number: NCT01435005.

Background: The primary purpose of this study was to determine associations of accelerometer-assessed moderate- to vigorous-intensity physical activity (MVPA) and sedentary time with health-related quality of life (HRQoL) and physical function and well-being in colon cancer survivors., Methods: Colon cancer survivors (N = 178) from Alberta, Canada (n = 92) and Western Australia (n = 86) completed a mailed survey that assessed HRQoL (Functional Assessment of Cancer Therapy-Colorectal), physical function and well-being (Trial Outcome Index-Colorectal), and relevant covariates. MVPA and sedentary time were assessed using the Actigraph GT3X+ accelerometer (60-second epochs) via a 7-day monitoring protocol. Average daily MVPA and sedentary time was corrected for wear time and then examined as quartiles., Results: Adjusting for relevant demographic, behavioral, and clinical covariates, a significant difference in HRQoL scores emerged between quartile 1 (Q1) and Q4 (M(diff) = 11.5, P = .038). For physical function and well-being, a significant difference emerged between Q1 and Q4 (M(diff) = 9.1, P = .009). For fatigue, a significant difference emerged between Q1 and Q4 (M(diff) = 7.1, P = .05). Significant differences were also observed for between Q1 and Q3 (M(diff) = 2.4, P = .041), and Q1 and Q4 (M(diff) = 3.5, P = .002) for colorectal cancer-specific symptoms. There were no statistically significant associations of sedentary time with HRQoL, physical function and well-being, fatigue, or colorectal cancer-specific symptoms., Conclusions: Objectively measured MVPA, but not sedentary time, was associated with better HRQoL, physical function and well-being, and colorectal cancer-specific symptoms in colon cancer survivors. For MVPA, differences met or exceeded contemporary cutpoints for determining clinically important differences., (© 2014 American Cancer Society.)

Background: Studies provide conflicting evidence for the protective effects of moderate-to-vigorous-intensity physical activity on depression. Recent evidence suggests that sedentary behaviors may also be associated with depression., Purpose: To examine the associations of accelerometer-derived moderate-to-vigorous-intensity physical activity and sedentary time with depression among a population-based sample., Methods: Cross-sectional study using 2,862 adults from the 2005-2006 US National Health and Nutrition Examination Survey. ActiGraph accelerometers were used to derive both moderate-to-vigorous-intensity physical activity and sedentary time., Results: Depression occurred in 6.8% of the sample. For moderate-to-vigorous-intensity physical activity, compared with those in quartile 1 (least active), significantly lower odds of depression were observed for those participants in quartiles 2 (OR=0.55, 95% CI, 0.34 to 0.89), 3 (OR=0.49, 95% CI, 0.26 to 0.93), and 4 (most active) (OR=0.37, 95% CI, 0.20 to 0.70) (p for trend p<0.01). In overweight/obese participants only, those in quartile 4 (most sedentary) had significantly higher odds for depression than those in quartile 1 (least sedentary) [quartile 3 vs 1 (OR=1.94, 95% CI, 1.01 to 3.68) and 4 vs 1 (OR=3.09, 95% CI, 1.25 to 7.68)]., Conclusion: The current study identified lower odds of depression were associated with increasing moderate-to-vigorous-intensity physical activity and decreasing sedentary time, at least within overweight/obese adults., (Copyright © 2011 Elsevier Inc. All rights reserved.)

Physical activity is well-established on the cancer survivorship research agenda, but prostate cancer survivors remain an understudied population. Additionally, the unique relationships between sedentary time and health outcomes have not yet been considered in this group. We examined the associations of accelerometer-assessed physical activity and sedentary time with waist circumference in 103 prostate cancer survivors from the National Health and Nutrition Examination Survey 2003-2004 and 2005-2006. Participants wore an Actigraph accelerometer for 7 days, and activity levels were summarised as moderate-to-vigorous intensity activity (accelerometer counts/minute ≥ 1952), light-intensity activity (counts/minute 100-1951) and sedentary time (counts/minute < 100). Moderate-to-vigorous intensity physical activity was inversely associated with waist circumference (β=-6.728, 95% CI: -12.267, -1.190, P= 0.020), equating to a top versus bottom quartile difference of 13.7 cm. No discernable relationship existed between light-intensity activity or sedentary time and adiposity. This is the first study to objectively measure the activity levels of prostate cancer survivors. Increasing moderate-to-vigorous activity may assist this population with weight management. More research into the relationships of light-intensity physical activity and sedentary behaviour with health outcomes among prostate cancer survivors is warranted, given the strong relationships seen in the broader population., (© 2010 Blackwell Publishing Ltd.)

Breast cancer is the most commonly diagnosed invasive malignancy and the second leading cause of cancer death in women. This chapter considers epidemiologic evidence regarding the association between physical activity and breast cancer risk from 73 studies conducted around the world. Across these studies there was a 25% average risk reduction amongst physically active women as compared to the least active women. The associations were strongest for recreational activity, for activity sustained over the lifetime or done after menopause, and for activity that is of moderate to vigorous intensity and performed regularly. There is also some evidence for a stronger effect of physical activity amongst postmenopausal women, women who are normal weight, have no family history of breast cancer, and are parous. It is likely that physical activity is associated with decreased breast cancer risk via multiple interrelated biologic pathways that may involve adiposity, sex hormones, insulin resistance, adipokines, and chronic inflammation. Future research should include prospective observational epidemiologic studies relating proposed biomarkers to breast cancer risk and also randomized controlled trials to examine how physical activity influences the proposed biomarkers. Exercise trials will provide more clarity regarding the appropriate type, dose, and timing of activity that relate to breast cancer risk reduction.

Background: Physical activity is a modifiable lifestyle risk factor that has the potential to reduce the risk of most major cancer sites., Methods: We examined the strength, consistency, dose-response and biological plausibility of an association between physical activity and risk of colon, breast, endometrium, lung, prostate, ovarian, gastric, rectal, pancreatic, bladder, testicular, kidney and haematological cancers. We also estimated the population-attributable risk (PAR) for physical inactivity and cancer in 15 European countries., Results: There is convincing or probable evidence for a beneficial effect of physical activity on the risk of colon, breast and endometrial cancers. The evidence is weaker for ovarian, lung and prostate cancers and generally either null or insufficient for all remaining cancers. Several hypothesised biological mechanisms include a likely effect of physical activity on insulin resistance, body composition, sex steroid hormones and a possible effect on vitamin D, adipokines, inflammation and immune function. Somewhere between 165,000 and 330,000 cases of the six major cancers (breast, colon, lung, prostate, endometrium and ovarian) could have been prevented in 2008 in Europe alone if the population had maintained sufficient levels of physical activity., Conclusion: There is strong and consistent evidence that physical activity reduces the risk of several of the major cancer sites, and that between 9% and 19% of cancer cases could be attributed to lack of sufficient physical activity in Europe. Public health recommendations for physical activity and cancer prevention generally suggest 30-60 min of moderate or vigorous-intensity activity done at least 5d per week., (Copyright © 2010 Elsevier Ltd. All rights reserved.)