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Purpose: To examine the association of strength training (ST) activity with impaired glucose metabolism (IGM) in Australian adults., Methods: On the basis of an oral glucose tolerance test, IGM (which includes impaired fasting glucose, impaired glucose tolerance, or newly diagnosed type 2 diabetes), was assessed in 5831 adults (mean age = 56.0 +/- 12.7 yr) without clinically diagnosed diabetes who participated in the 2004–2005 Australian Diabetes, Obesity and Lifestyle Study (AusDiab). Meeting the current ST guideline was based on reporting ST at least two times per week (frequency) or > or = 40 min x wk(-1) in total (duration). Multiple logistic regression analyses examined associations of self-reported ST frequency and duration with IGM., Results: After adjustment for known confounding factors and total moderate- to vigorous-intensity leisure time exercise, the odds ratio (OR) of IGM was 0.73 (95% confidence interval [CI] = 0.59–0.91, P < or = 0.005) in those who met the ST frequency guideline (two or more times per week) and 0.69 (95% CI = 0.55–0.87, P < or = 0.01) in those who met the ST duration guideline (> or =40 min x wk(-1)). Those who achieved both the recommended frequency and duration of ST had 24% lower odds of IGM. There was also evidence that a moderate frequency (once a week) and duration (10–39 min x wk(-1)) of ST reduced the odds of IGM (OR frequency = 0.53, 95% CI = 0.51–0.81, P e 0.01; OR duration = 0.72, 95% CI = 0.52–1.00, P < or = 0.05)., Conclusions: These findings support the importance of including ST activity, at a frequency of at least once per week, within exercise management recommendations for the maintenance of favorable metabolic health, particularly as it may contribute to reducing the risk of developing type 2 diabetes mellitus.

Purpose: to examine the associations of physical activity and television (TV) viewing time with retinal vascular caliber in Australian adults., Methods: a total of 2024 adults aged 25 yr or older without known diabetes in the Australian Diabetes, Obesity, and Lifestyle Study (AusDiab, 1999-2000), a population-based cross-sectional study, were evaluated. Retinal vascular calibers (both arteriolar and venular calibers) were measured from digital retinal photographs using a computer-assisted method and were summarized into central retinal artery and vein equivalents. Self-reported physical activity time and TV viewing time were obtained using interviewer-administered questionnaires., Results: for physical activity, no statistically significant multivariate relationships emerged for men or for women. After adjusting for confounders (age, sex, education, cigarette smoking, diet quality, waist circumference, systolic blood pressure, plasma glucose levels, serum fibrinogen, serum triglyceride, and physical activity time), men who watched TV for at least 2 h·d had a venular caliber that was 4.71 microm (95% confidence interval = 1.37-8.04 microm, P = 0.006) wider compared with those watching <2 h·d of TV. No significant association with venular caliber was noted in women., Conclusions: these findings provide the first evidence of an association between TV viewing time (a common, leisure time sedentary behavior) and retinal microcirculation. Further research is needed to examine these associations in different populations and by using more comprehensive physical activity and sedentary behavior measures.

Purpose: Television viewing time, independent of leisure time physical activity, has cross-sectional relationships with the metabolic syndrome and its individual components. We examined whether baseline and 5-yr changes in self-reported television viewing time are associated with changes in continuous biomarkers of cardiometabolic risk (waist circumference, triglycerides, HDL-cholesterol, systolic and diastolic blood pressure, fasting plasma glucose, and a clustered cardiometabolic risk score) in Australian adults., Methods: The Australian Diabetes, Obesity and Lifestyle Study (AusDiab) is a prospective, population-based cohort study with biological, behavioral, and demographic measures collected in 1999-2000 and 2004-2005. Noninstitutionalized adults aged > or =25 yr were measured at baseline (11,247; 55% of those completing an initial household interview); 6400 took part in the 5-yr follow-up biomedical examination, and 3846 met the inclusion criteria for this analysis. Multiple linear regression analysis was used, and unstandardized B coefficients (95% confidence intervals (CI)) are provided., Results: Baseline television viewing time (10 h.wk-1 unit) was not significantly associated with change in any of the biomarkers of cardiometabolic risk. Increases in television viewing time over 5 yr (10 h.wk-1 unit) were associated with increases in waist circumference (men: 0.43 cm, 95% CI = 0.08-0.78 cm, P = 0.02; women: 0.68 cm, 95% CI = 0.30-1.05, P < 0.001), diastolic blood pressure (women: 0.47 mm Hg, 95% CI = 0.02-0.92 mm Hg, P = 0.04), and the clustered cardiometabolic risk score (women: 0.03, 95% CI = 0.01-0.05, P = 0.007). These associations were independent of baseline television viewing time and baseline and change in physical activity and other potential confounders., Conclusions: These findings indicate that an increase in television viewing time is associated with adverse cardiometabolic biomarker changes. Further prospective studies using objective measures of several sedentary behaviors are required to confirm causality of the associations found.

Background: Asian Indians show an increased risk of non-insulin-dependent diabetes mellitus (NIDDM) and coronary heart disease, together with adverse fat distribution and hyperinsulinaemia relative to other ethnic groups. Using population-based data, we investigated the question of whether the adverse fat distribution observed in Indians can be explained by differences in behavioural risk factor levels. We have examined the question of whether ethnic differences in fat distribution are responsible for the unfavourable risk factor profile of Indians., Subjects and Methods: Fat distribution (waist: hip ratio) was compared in population-based samples of Asian Indian (n = 4394), Creole (n = 1746), and Chinese (n = 425) Mauritians, after controlling for body mass index and other factors. The contribution of this ratio to ethnic differences in cardiovascular disease risk factors and the role of fasting insulin concentrations were also determined., Results: Indian men had the highest mean waist: hip ratio, despite having the lowest body mass index. In Indian women the mean waist: hip ratio and body mass index were intermediate between those of Chinese and Creole women. Indians of both sexes had low levels of high-density lipoprotein (HDL) cholesterol and HDL: total cholesterol compared with Creoles or Chinese, whereas triglycerides levels were highest in Indian men but intermediate in Indian women. Mean fasting and 2 h insulin concentrations were not consistently highest in the Indian subgroups. Blood pressure and serum urate levels were lowest in Indians of both sexes and Indian women also had lower total cholesterol concentrations than either Creoles or Chinese. The elevated waist: hip ratio in Indians was not explained by differences in physical activity, cigarette smoking, or alcohol consumption and the differences in this ratio (and insulin levels) did not explain the observed ethnic differences in metabolic parameters., Conclusions: The susceptibility of Indians to abdominal obesity contributed to the less desirable levels of some, but not all, cardiovascular risk factors. Ethnic differences in cardiovascular risk factors in Mauritians were not explained by differences in abdominal obesity, serum insulin or behavioural risk factors. These data suggest that it is over-simplistic to ascribe the adverse cardiovascular risk factor profile commonly observed in Asian Indians to a tendency to abdominal obesity.