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Sleep is essential to life. Accurate measurement and classification of sleep/wake and sleep stages is important in clinical studies for sleep disorder diagnoses and in the interpretation of data from consumer devices for monitoring physical and mental well-being. Existing non-polysomnography sleep classification techniques mainly rely on heuristic methods developed in relatively small cohorts. Thus, we aimed to establish the accuracy of wrist-worn accelerometers for sleep stage classification and subsequently describe the association between sleep duration and efficiency (proportion of total time asleep when in bed) with mortality outcomes. We developed a self-supervised deep neural network for sleep stage classification using concurrent laboratory-based polysomnography and accelerometry. After exclusion, 1113 participant nights of data were used for training. The difference between polysomnography and the model classifications on the external validation was 48.2 min (95% limits of agreement (LoA): −50.3 to 146.8 min) for total sleep duration, −17.1 min for REM duration (95% LoA: −56.7 to 91.0 min) and 31.1 min (95% LoA: −67.3 to 129.5 min) for NREM duration. The sleep classifier was deployed in the UK Biobank with ~100,000 participants to study the association of sleep duration and sleep efficiency with all-cause mortality. Among 66,262 UK Biobank participants, 1644 mortality events were observed. Short sleepers (<6 h) had a higher risk of mortality compared to participants with normal sleep duration 6–7.9 h, regardless of whether they had low sleep efficiency (Hazard ratios (HRs): 1.36; 95% confidence intervals (CIs): 1.18 to 1.58) or high sleep efficiency (HRs: 1.29; 95% CIs: 1.04–1.61). Deep-learning-based sleep classification using accelerometers has a fair to moderate agreement with polysomnography. Our findings suggest that having short overnight sleep confers mortality risk irrespective of sleep continuity. [ABSTRACT FROM AUTHOR]

Mental health conditions confer considerable global disease burden in young adults, who are also the highest demographic to work shifts, and of whom 20% meet criteria for a sleep disorder. We aimed to establish the relationship between the combined effect of shift work and sleep disorders, and mental health. The Raine Study is the only longitudinal, population-based birth cohort in the world with gold-standard, Level 1 measurement of sleep (polysomnography, PSG) collected in early adulthood. Participants (aged 22y) underwent in-laboratory PSG and completed detailed sleep questionnaires. Multivariable adjusted robust linear regression models were conducted to explore associations with anxiety (GAD7) and depression (PHQ9), adjusted for sex, health comorbidities, and work hours/week. Data were from 660 employed young adults (27.3% shift workers). At least one clinically significant sleep disorder was present in 18% of shift workers (day, evening and night shifts) and 21% of non-shift workers (p = 0.51); 80% were undiagnosed. Scores for anxiety and depression were not different between shift and non-shift workers (p = 0.29 and p = 0.82); but were higher in those with a sleep disorder than those without (Md(IQR) anxiety: 7.0(4.0–10.0) vs 4.0(1.0–6.0)), and depression: (9.0(5.0–13.0) vs 4.0(2.0–6.0)). Considering evening and night shift workers only (i.e. excluding day shift workers) revealed an interaction between shift work and sleep disorder status for anxiety (p = 0.021), but not depression (p = 0.96), with anxiety scores being highest in those shift workers with a sleep disorder (Md(IQR) 8.5(4.0–12.2). We have shown that clinical sleep disorders are common in young workers and are largely undiagnosed. Measures of mental health do not appear be different between shift and non-shift workers. These findings indicate that the identification and treatment of clinical sleep disorders should be prioritised for young workers as these sleep disorders, rather than shift work per se, are associated with poorer mental health. These negative mental health effects appear to be greatest in those who work evening and/or night shift and have a sleep disorder. [ABSTRACT FROM AUTHOR]

Background: Skeletal muscle loss is common in advanced cancer and is associated with negative outcomes. In malignant pleural mesothelioma (MPM), no study has reported body composition changes or factors associated with these changes. This study aimed to describe changes in body composition over time and its relationship with activity levels, dietary intake and survival.Methods: The study was a secondary analysis of data collected from a longitudinal observational study of patients with MPM. Participants completed 3-month assessments for up to 18 months. Participants with two dual-energy x-ray absorptiometry (DXA) scans were included. Changes in appendicular skeletal muscle mass (ASM) and total fat mass were used to categorise participants into phenotypes. Activity levels were measured with an ActiGraph GT3X+ accelerometer and energy and protein intake was measured with a 3-day food record and 24-h recall.Results: Eighteen participants were included (89% men, mean age 68.9 ± 7.1 years). Median time between DXA was 91 [IQR 84-118] days. Compared to participants with ASM maintenance (n = 9), fewer participants with ASM loss (n = 9) survived ≥12 months from follow-up (p = 0.002). Participants with ASM loss increased sedentary time (p = 0.028) and decreased light activity (p = 0.028) and step count (p = 0.008). Activity levels did not change in participants with ASM maintenance (p > 0.05). Energy and protein intake did not change in either group (p > 0.05).Conclusions: Muscle loss was associated with poorer survival and decreased activity levels. Interventions that improve physical activity or muscle mass could benefit patients with MPM. [ABSTRACT FROM AUTHOR]

Objectives and design: This study aimed to understand the longitudinal relationship between C-reactive protein (CRP) and body mass index (BMI) from adolescence to early adulthood. Methods: CRP and BMI were collected from participants of the Raine Study Gen2 at 14-, 17-, 20- and 22-year follow-ups (n = 1312). A dual trajectory analysis was conducted to assess the association between CRP and BMI trajectories, providing conditional probabilities of membership of CRP trajectory membership given BMI trajectory membership. Best model fit was assessed by systematically fitting two to eight trajectory groups with linear and quadratic terms and comparing models according to the Bayesian Information Criterion statistic. Results: The three CRP trajectories were; "stable-low" (71.0%), "low-to-high" (13.8%) and "stable-high" (15.2%). Participants in a "high-increasing" BMI trajectory had a higher probability of being in the "stable-high" CRP trajectory (60.4% of participants). In contrast, individuals in the "medium-increasing" BMI trajectory did not have a significantly increased probability of being in the "stable-high" CRP trajectory. Conclusions: These findings support that chronic sub-clinical inflammation is present through adolescence into early adulthood in some individuals. Targeting chronic sub-clinical inflammation though obesity prevention strategies may be important for improving future health outcomes. [ABSTRACT FROM AUTHOR]

Myopia (near-sightedness) is an important public health issue. Spending more time outdoors can prevent myopia but the long-term association between this exposure and myopia has not been well characterised. We investigated the relationship between time spent outdoors in childhood, adolescence and young adulthood and risk of myopia in young adulthood. The Kidskin Young Adult Myopia Study (KYAMS) was a follow-up of the Kidskin Study, a sun exposure-intervention study of 1776 children aged 6–12 years. Myopia status was assessed in 303 (17.6%) KYAMS participants (aged 25–30 years) and several subjective and objective measures of time spent outdoors were collected in childhood (8–12 years) and adulthood. Index measures of total, childhood and recent time spent outdoors were developed using confirmatory factor analysis. Logistic regression was used to assess the association between a 0.1-unit change in the time outdoor indices and risk of myopia after adjusting for sex, education, outdoor occupation, parental myopia, parental education, ancestry and Kidskin Study intervention group. Spending more time outdoors during childhood was associated with reduced risk of myopia in young adulthood (multivariable odds ratio [OR] 0.82, 95% confidence interval [CI] 0.69, 0.98). Spending more time outdoors in later adolescence and young adulthood was associated with reduced risk of late-onset myopia (≥ 15 years of age, multivariable OR 0.79, 95% CI 0.64, 0.98). Spending more time outdoors in both childhood and adolescence was associated with less myopia in young adulthood. [ABSTRACT FROM AUTHOR]

Young children are increasingly using mobile technology, with potential for positive and negative developmental consequences. Parents are responsible to guide children in their use of technology based on recommendations and guidelines. Guidelines for screen use in young children have been based on little empirical information on contemporary screen use. This study surveyed parents of young children (n = 96, mean child age 3.0, SD 1.0 years) from three settings (Australia, United States) to test the reliability and validity of a new tool to capture richer data on technology use within a techno-microsystem. The TechU-Q demonstrated reasonable test-retest reliability and face and construct validity. Young children averaged more than 60 min per day of total technology use, mostly using TV, tablet computers, and mobile phones. The primary purposes for child use were educational and watching videos. Parental attitudes towards technology and parent use were associated with their child's use. Future guidelines should utilize detailed descriptions of technology use by device and purpose to provide more relevant advice on technology use for young children. Highlights: The TechU-Q was found to be reliable and valid for assessing young children's and parents' technology use. Child technology use was associated with parent technology use. Parents had generally neutral attitudes towards young children's technology use, with primary concerns related to technology use decreasing physical activity and increasing sedentary time. [ABSTRACT FROM AUTHOR]

Background: Accurate and detailed measurement of a dancer’s training volume is a key requirement to understanding the relationship between a dancer’s pain and training volume. Currently, no system capable of quantifying a dancer’s training volume, with respect to specific movement activities, exists. The application of machine learning models to wearable sensor data for human activity recognition in sport has previously been applied to cricket, tennis and rugby. Thus, the purpose of this study was to develop a human activity recognition system using wearable sensor data to accurately identify key ballet movements (jumping and lifting the leg). Our primary objective was to determine if machine learning can accurately identify key ballet movements during dance training. The secondary objective was to determine the influence of the location and number of sensors on accuracy. Results: Convolutional neural networks were applied to develop two models for every combination of six sensors (6, 5, 4, 3, etc.) with and without the inclusion of transition movements. At the first level of classification, including data from all sensors, without transitions, the model performed with 97.8% accuracy. The degree of accuracy reduced at the second (83.0%) and third (75.1%) levels of classification. The degree of accuracy reduced with inclusion of transitions, reduction in the number of sensors and various sensor combinations. Conclusion: The models developed were robust enough to identify jumping and leg lifting tasks in real-world exposures in dancers. The system provides a novel method for measuring dancer training volume through quantification of specific movement tasks. Such a system can be used to further understand the relationship between dancers’ pain and training volume and for athlete monitoring systems. Further, this provides a proof of concept which can be easily translated to other lower limb dominant sporting activities [ABSTRACT FROM AUTHOR]

Background/objectives: Malignant pleural mesothelioma (MPM) is an incurable cancer and optimizing daily physical activity and quality of life are key goals of patient management. Little is known about the prevalence of pre-sarcopenia and malnutrition in MPM or their associations with patient outcomes. This study aimed to determine the prevalence of pre-sarcopenia and malnutrition in MPM and investigate if activity levels and quality of life differed according to body composition and nutritional status.Subjects/methods: Patients with a diagnosis of MPM were recruited. Pre-sarcopenia was defined as low appendicular skeletal muscle mass (≤ 7.26 kg/m2 for men and ≤ 5.45 kg/m2 for women), measured by dual energy X-ray absorptiometry. Malnutrition was defined as a rating of B or C on the Patient-Generated Subjective Global Assessment. Outcome measures included objective activity levels (Actigraph GT3X) and health-related quality of life (HRQoL; Functional Assessment of Cancer Therapy General).Results: Sixty-one people participated (79% male, median age 69 [IQR 62-74] years and median BMI 25.8 [IQR 24.3-28.4] kg/m2). Fifty-four percent were pre-sarcopenic and 38% were malnourished. Percent of time spent in light activity/day was lower in participants with pre-sarcopenia compared with non-sarcopenic participants (median 25.4 [IQR 19.8-32.1]% vs. 32.3 [27.1-35.6]%; p = 0.008). Participants with malnutrition had poorer HRQoL than well-nourished participants (mean 69.0 (16.3) vs. 84.4 (13.3); p < 0.001).Conclusion: Participants with MPM had high rates of pre-sarcopenia and malnutrition. Pre-sarcopenia was associated with poorer activity levels, whilst malnutrition was associated with poorer quality of life. Interventions that aim to address reduced muscle mass and weight loss, should be tested in MPM to assess their impact on patient outcomes. [ABSTRACT FROM AUTHOR]

Introduction and hypothesis: Urogenital symptoms are prevalent in older women, but there is little data available on the prevalence, bother, impact and associations with low back pain (LBP), obesity, parity, mental health (MH) and quality of life (QOL) in young women. Our aim was to determine the prevalence, bother and impact of urogenital symptoms and to explore associations with LBP, obesity, parity, MH and QOL in 22 year-old women.Methods: This was a cross-sectional evaluation using data collected from 588 women in the Raine Study, a pregnancy cohort in which participants have been regularly followed up from birth until 22 years. Data was analysed using descriptive statistics, univariate comparisons and linear regression models.Results: Prevalence of urogenital symptoms were stress urinary incontinence (SUI) 6.3%, mixed urinary incontinence (MUI) 11.5%, leakage of drops 5.8%, urge urinary incontinence (UUI) 5.3%, bothersome urinary frequency 41.5%, difficulty emptying 11.8% and urogenital pain 22.9%. Urinary frequency, MUI, difficulty emptying and urogenital pain were most bothersome, whilst difficulty emptying and urogenital pain were associated with greatest impact. Urinary frequency, SUI, leakage of drops, difficulty emptying and urogenital pain were associated with current LBP and LBP ever. Difficulty emptying and urogenital pain were associated with chronic LBP. Urogenital symptoms were not associated with obesity or parity. Women with urogenital symptoms had significantly poorer scores on the Mental Component Score of the Short Form Health Survey (SF)-12 and all aspects of the Depression Anxiety Stress Score.Conclusions: Urogenital symptoms are prevalent in young women, bothersome for some and are associated with LBP, poorer MH and reduced QOL. [ABSTRACT FROM AUTHOR]

Purpose: To identify “activity phenotypes” from accelerometer-derived activity characteristics among young adults.Methods: Participants were young adults (n = 628, mean age, 22.1, SD 0.6) in the Raine Study in Western Australia. Sex-specific latent class analyses identified sub-groups using eight indicators derived from 7-day hip-worn Actigraph GT3X+ accelerometers: daily steps, total daily moderate-to-vigorous physical activity (MVPA), MVPA variation, MVPA intensity, MVPA bout duration, sedentary-to-light ratio, sedentary-to-light ratio variation, and sedentary bout duration.Results: Five activity phenotypes were identified for women (n = 324) and men (n = 304). Activity phenotype 1 for both women (35%) and men (30%) represented average activity characteristics. Phenotype 2 for women (17%) and men (16%) was characterized by below average total activity and MVPA (10.6 and 16.7 min of MVPA/day, women and men respectively). Phenotype 3 for women (15%) and men (23%) was characterized by below average total physical activity, average MVPA (32.6 and 36.5 min/day), high sedentary-light ratio and long sedentary bouts. Phenotype 4 differed between women (29%) and men (18%) but both had low sedentary-to-light ratios and shorter sedentary bouts. Finally, phenotype 5 in both women (4%) and men (12%) was characterized by extreme MVPA metrics (81.3 and 96.1 min/day).Conclusions: Five activity phenotypes were identified for each gender in this population of young adults which can help design targeted interventions to enhance or modulate activity phenotypes. [ABSTRACT FROM AUTHOR]

Purpose: Little is known about the relationship between health-related quality of life (HRQoL), pelvic floor dysfunction (PFD), and modifiable lifestyle and physiological factors for ovarian cancer survivors (OCS). The primary aim of the study was to compare post-treatment advanced-stage OCS with age-matched controls on measures of HRQoL and PFD. The secondary aim was to examine associations between HRQoL, PFD, objective activity behaviors, physical function, and body composition in OCS.Methods: Twenty advanced-stage OCS and 20 controls completed questionnaires assessing HRQoL (SF-36) and PFD (Australian Pelvic Floor Questionnaire), and underwent objective assessments of activity behavior (7-day accelerometry), physical function (400-m walk, repeated chair rise, 6-m usual-pace walk, one-repetition maximum chest press, and single-leg extension), and body composition (dual-energy x-ray absorptiometry).Results: Compared to controls, OCS had worse physical HRQoL (− 4.3 median difference, p = 0.013), but equivalent self-reported PFD, indicated by combined bladder, bowel, and pelvic organ prolapse symptoms (0.89 mean difference, p = 0.277). In OCS, physical HRQoL was significantly negatively associated with PFD (r = 0.468, p = 0.043). Decreased physical HRQoL and increased PFD were significantly associated with less moderate-to-vigorous physical activity in ≥ 10-min bouts (ρ = 0.627, p = 0.003; ρ = − 0.457, p = 0.049), more sedentary time (r = − 0.449, p = 0.047; r = 0.479, p = 0.038), and slower 400-m walk time (ρ = − 0.565, p = 0.022; ρ = 0.504, p = 0.028).Conclusions: Post-treatment advanced-stage OCS have decreased physical HRQoL, which is associated with modifiable factors such as worse PFD, less moderate-to-vigorous physical activity, more sedentary time, and decreased objective physical function. This highlights the need for ongoing supportive care and multidisciplinary interventions after first-line ovarian cancer treatment. [ABSTRACT FROM AUTHOR]

Purpose: The average Australian working week in middle-aged and older workers exceeds government recommendations. Long working weeks are associated with poor health outcomes; however, the relationship between long working weeks and health in young Australian workers is unknown.Methods: Data were drawn from the 22-year follow-up of the Western Australian Pregnancy Cohort (Raine) Study in Perth, Western Australia. Information was available from 873 young adults about working hours per week, shift work and sleep duration. Blood samples provided measures of cardiometabolic risk (CMR) factors.Results: Almost one-third (32.8%) of young workers reported > 38 h working weeks. This was commonly reported in mining and construction industries for males; health and social assistance, mining and retail trade industries for females. CMR factors including increased waist circumference, higher fasting plasma glucose and reduced HDL cholesterol were associated with > 38 h working weeks. These relationships were not moderated by gender or by BMI for glucose and HDL cholesterol. Total sleep time was significantly lower in both male and female workers reporting > 38 h working weeks, but did not mediate the relationships seen with CMR factors.Conclusions: These findings point to early associations between > 38 h working weeks and CMR risk, and highlight the potential benefit of making young employees aware of the health associations with working arrangements to reduce the longer-term relationships seen with working hours and poor cardiometabolic health in population studies. [ABSTRACT FROM AUTHOR]

Accurate measurement of time at lights out is essential for calculation of several measures of sleep in wrist-activity monitors. While some devices use subjective reporting of time of lights out from a sleep diary, others utilise an automated proprietary scoring algorithm to calculate time at lights out, thereby negating the need for a sleep diary. This study aimed to compare sleep measures from two such devices to polysomnography (PSG) measures (In laboratory) and against each other when worn at home (At home). Fifty middle-aged adults from the Raine Study underwent overnight PSG during which they wore an ActiGraph™ and a Readiband™. They also wore both devices at home for 7 nights. The Readiband uses an automated proprietary algorithm to determine time at lights out whereas the ActiGraph requires completion of a sleep diary noting this time. In laboratory, compared to PSG: Readiband underestimated time at lights out, sleep onset, and wake after sleep onset, overestimated sleep latency and duration ( p < 0.001 for all); while ActiGraph underestimated sleep latency and wake after sleep onset and overestimated sleep efficiency and duration ( p < 0.001 for all). Similar differences between devices were observed on the laboratory night and when at home. In conclusion, an automated algorithm such as the Readiband may be used in the same capacity as the ActiGraph for the collection of sleep measures including time at sleep onset, sleep duration and time at wake. However, Readiband and ActiGraph measures of sleep latency, efficiency and wake after sleep onset should be interpreted with caution. [ABSTRACT FROM AUTHOR]

Objectives: Initiatives to reduce office-workplace sitting are proliferating, but the impact of pre-existing musculoskeletal symptoms on their effectiveness has not been determined. We assessed the influence of musculoskeletal symptoms on the outcomes of a workplace sitting intervention. Methods: Baseline and 3-month data from a cluster-randomized controlled trial of a workplace sitting intervention ( Stand Up Victoria; trial registration number ACTRN12611000742976) were used. Office workers ( n = 231) from 14 work teams within one organisation were randomised (by worksite) to a multicomponent program with individual-, organisational-, and environmental-level (sit-stand workstations) change strategies; or, to a control condition (no intervention). Musculoskeletal symptoms in the low-back, upper and lower extremities (present/absent) were assessed through self-report. Linear regression models tested the moderation by baseline musculoskeletal symptoms of intervention effects on workplace sitting and standing time and on sitting and standing bout durations, assessed by the activPAL3™ activity monitor. Results: There were significant reductions in sitting and increased standing at work ( p < 0.05). However, effects varied significantly by the presence of pre-existing low-back (but not other) symptoms, with greater benefit being seen in those without symptoms. Effects on sitting time and sitting bout duration were weaker in those with low-back symptoms compared to those without by 34.6 [95% CI (0.9; 68.3)] min/8-h workday and 5.1 [95% CI (0.2; 9.9)] min, respectively. Comparable effects were seen for standing. Conclusion: Low-back symptoms may impact on the extent to which office workers change their workplace sitting and standing time. A prudent next step to improve the effectiveness of workplace sitting-reduction initiatives such as Stand Up Victoria may be to assess and address the needs of those who displayed comparatively limited behaviour change, namely those with pre-existing low-back discomfort. [ABSTRACT FROM AUTHOR]

Purpose: Malignant pleural effusion (MPE) affects 1 million people worldwide annually and can significantly impair physical activity. Accelerometry is a validated method of objectively assessing physical activity. The purpose of this study was to determine the compliance in patients with MPE to accelerometry and describe their activity.Methods: Patients with MPE wore an Actigraph GT3X accelerometer over a 7-day continuous wear protocol. Compliance was measured as the percent of patients who had ≥4 valid days (i.e., 8-h/day of waking wear-time). Eastern Cooperative Oncology Group performance status was documented the day of actigraphy initialization.Results: Forty-six patients with MPE received accelerometers; 44 (95.7%) returned their device. No complications were reported on their use. Forty subjects (90.9%) had ≥4 valid days of wear-time. Patients spent most of their waking hours sedentary [mean 11.0 h (SD 1.95)], with limited participation in moderate and vigorous physical activity [mean 9.5 min (SD 14.16)]. Compared to patients with better performance status (n = 32), patients with poorer performance status (n = 11) spent significantly more hours/day sedentary [mean difference 2.1 (CI 0.86-3.32); p = 0.001], as did those who survived <3 months (n = 5) compared to >12 months (n = 27) [mean difference 2.6 (CI 0.49-4.77); p = 0.013).Conclusion: Accelerometry was applied successfully in patients with MPE with high compliance and no adverse events. This is the first reported objectively measured physical activity in patients with MPE and revealed high sedentary behavior and low physical activity. The data reflected patient performance status and discriminated between survival groups. Accelerometry can provide a useful measure for future interventional studies in patients with MPE. [ABSTRACT FROM AUTHOR]

Wrist actigraphy is commonly used to measure sleep, and hip actigraphy is commonly used to measure activity. It is unclear whether hip-based actigraphy can be used to measure sleep. This study assessed the validity of wrist actigraphy and hip actigraphy compared to polysomnography ( PSG) for the measurement of sleep. 108 healthy young adults (22.7 ± 0.2 years) wore hip and wrist GTX3+ Actigraph during overnight PSG. Measurements of total sleep time ( TST), sleep efficiency ( SE), sleep onset latency ( SOL) and wake after sleep onset ( WASO) were derived and compared between wrist actigraphy, hip actigraphy and PSG. Sensitivity, specificity and accuracy of wrist actigraphy and hip actigraphy for each variable were derived from epoch-by-epoch comparison to PSG. Compared to PSG: TST and SE were similar by wrist actigraphy but overestimated by hip actigraphy (both by 14%); SOL was underestimated by wrist actigraphy and hip actigraphy (by 39 and 80%, respectively); WASO was overestimated by wrist actigraphy and underestimated by hip actigraphy (by 34 and 65%, respectively). Compared to PSG the sensitivity, specificity and accuracy of wrist actigraphy were 90, 46 and 84%, respectively; and of hip actigraphy were 99, 14 and 86%, respectively. This study showed that using existing algorithms, a GTX3+ Actigraph worn on the hip does not provide valid or accurate measures of sleep, mainly due to poor wake detection. Relative to the hip, a wrist worn GTX3+ Actigraph provided more valid measures of sleep, but with only moderate capability to detect periods of wake during the sleep period. [ABSTRACT FROM AUTHOR]

Past studies on work-related musculoskeletal disorders (WMSD) have reported increased median muscle activities in terms of 50th% of amplitude probability distribution function (APDF), and this was thought to be a manifestation of altered motor control--an important mechanism contributing to WMSD. The present study aimed to examine whether such altered motor control was also present in other parameters of APDF--the 10th and 90th% values, which can be considered indicators of the low and high measures of muscle activity. The difference between 10th and 90th% APDF can be considered an indicator of the variation in muscle activity amplitude (the "APDF range"). Surface electromyography was examined in female office workers as Case (n = 21) and Control (n = 18) subjects. The APDF variables were measured in cervical erector spinae (CES) and upper trapezius (UT) muscles during typing, mousing and type-and-mouse, for 20 min each. The Case Group had significantly higher CES activity in the 10th, 90th% and APDF range compared to Controls. The UT muscles showed similar trends but the between-group differences were not statistically significant. These results have demonstrated the robustness of the APDF variables as sensitive indicators of motor control variations in symptomatic subjects with musculoskeletal disorders. [ABSTRACT FROM AUTHOR]