Behavioural compensatory adjustments to exercise training in overweight women

<b>Purpose:</b> To examine extent to which changes in non-exercise physical activity contribute to individual differences in body fat loss induced by exercise programs. <b>Methods:</b> Thirty four overweight/obese sedentary women (age: 31.7 +/- 8.1 years, BMI: 29.3 +/- 4.3 kg m-2) exercised for 8 weeks. Body composition, total energy expenditure (TEE), exercise EE (ExEE), activity EE (AEE) calculated as energy expenditure of all active activities minus ExEE, sedentary EE (SEDEE), sleeping EE (SEE), and energy intake were determined before and during the last week of the exercise intervention. <b>Results:</b> Over the 8-week exercise program net ExEE was 30.2 +/- 12.6 MJ and based on this, body fat loss was predicted to be 0.8 +/- 0.2 kg. For the group as a whole, change in body fat (-0.0 +/- 0.2 kg) was not significant but individual body fat changes ranged from -3.2 kg to +2.6 kg. Eleven participants achieved equal or more than the predicted body fat loss and were classified as 'Responders' and 23 subjects achieved less than the predicted fat loss and were classified as 'Non-responders'. In the group as a whole, daily TEE was increased by 0.62 +/- 0.30 MJ (p<0.05) and the change tended to be different between groups (Responders, +1.44 +/- 0.49 MJ; Non-responders, +0.29 +/- 0.36 MJ, p=0.08). Changes in daily AEE of Responders and Non-responders differed significantly between groups (Responders, +0.79 +/- 0.50 MJ; Non-responders, -0.62 +/- 0.39 MJ, p<0.05). There were no differences between Responders and Non-responders for changes in SEDEE and SEE or energy intake. <b>Conclusion:</b> Overweight and obese women who during exercise intervention achieve lower than predicted fat loss are compensating by being less active outside exercise sessions

Association between grip strength and diabetes prevalence in black, South Asian, and white European ethnic groups: a cross-sectional study of 418,656 UK Biobank participants

Aims: To quantify the extent to which ethnic differences in muscular strength might account for the substantially higher prevalence of diabetes in black and South-Asian compared with white European adults. Methods: This cross-sectional study used baseline data from the UK Biobank study on 418 656 white European, black and South-Asian participants, aged 40–69 years, who had complete data on diabetes status and hand-grip strength. Associations between hand-grip strength and diabetes were assessed using logistic regression and were adjusted for potential confounding factors. Results: Lower grip strength was associated with higher prevalence of diabetes, independent of confounding factors, across all ethnicities in both men and women. Diabetes prevalence was approximately three- to fourfold higher in South-Asian and two- to threefold higher in black participants compared with white European participants across all levels of grip strength, but grip strength in South-Asian men and women was ~5–6 kg lower than in the other ethnic groups. Thus, the attributable risk for diabetes associated with low grip strength was substantially higher in South-Asian participants (3.9 and 4.2 cases per 100 men and women, respectively) than in white participants (2.0 and 0.6 cases per 100 men and women, respectively). Attributable risk associated with low grip strength was also high in black men (4.3 cases) but not in black women (0.4 cases). Conclusions: Low strength is associated with a disproportionately large number of diabetes cases in South-Asian men and women and in black men. Trials are needed to determine whether interventions to improve strength in these groups could help reduce ethnic inequalities in diabetes prevalence

The association between driving time and unhealthy lifestyles: a cross-sectional, general population study of 386 493 UK Biobank participants

Background: Driving is a common type of sedentary behaviour; an independent risk factor for poor health. The study explores whether driving is also associated with other unhealthy lifestyle factors. Methods: In a cross-sectional study of UK Biobank participants, driving time was treated as an ordinal variable and other lifestyle factors dichotomized into low/high risk based on guidelines. The associations were explored using chi-square tests for trend and binary logistic regression. Results: Of the 386 493 participants who drove, 153 717 (39.8%) drove <1 h/day; 140 140 (36.3%) 1 h/day; 60 973 (15.8%) 2 h/day; and 31 663 (8.2%) ≥3 h/day. Following adjustment for potential confounders, driving ≥3 h/day was associated with being overweight/obese (OR = 1.74, 95% CI: 1.64–1.85), smoking (OR = 1.48, 95% CI: 1.37–1.63), insufficient sleep (1.70, 95% CI: 1.61–1.80), low fruit/vegetable intake (OR = 1.26, 95% CI: 1.18–1.35) and low physical activity (OR = 1.05, 95% CI: 1.00–1.11), with dose relationships for the first three, but was not associated with higher alcohol consumption (OR = 0.94, 95% CI: 0.87–1.02). Conclusions: Sedentary behaviour, such as driving, is known to have an independent association with adverse health outcomes. It may have additional impact mediated through its effect on other aspects of lifestyle. People with long driving times are at higher risk and might benefit from targeted interventions

Associations of dietary protein intake with fat free mass and grip strength: cross-sectional study in 146,816 UK Biobank participants

Adequate dietary protein intake is important for the maintenance of fat-free mass (FFM) and muscle strength: optimal requirements remain unknown. The aim of the current study was to explore the associations of protein intake with FFM and grip strength. We used baseline data from the UK Biobank (146,816 participants aged 40-69 years with data collected 2007-2010 across the UK) to examine the associations of protein intake with FFM and grip strength. Protein intake was positively associated with FFM (men 5.1% [95% CI: 5.0; 5.2] and women 7.7% [95% CI: 7.7; 7.8]) and grip strength (men 0.076 kg/kg [95% CI: 0.074; 0.078] and women 0.074 kg/kg [95% CI: 0.073; 0.076]) per 0.5 grams per kg body mass per day (g/kg/day) increment in protein intake. FFM and grip strength were higher with higher intakes across the full range of intakes, i.e. highest in those reporting consuming > 2.0 g/grams per kg/day independently of socio-demographics, other dietary measures, physical activity and comorbidities. FFM and grip strength were lower with age, but this association did not differ by protein intake categories (P > 0.05). Current recommendation for all adults (40-69 years) for protein intake (0.8 grams per kg body mass per day) may need to be increased to optimise FFM and grip strength

Fruit juice: just another sugary drink?

No abstract available

Physical activity and prevention of type 2 diabetes mellitus

The worldwide prevalence of type 2 diabetes mellitus is increasing at a rapid rate, predominantly because of changes in environmental factors interacting with individual genetic susceptibility to the disease. Data from 20 longitudinal cohort studies present a consistent picture indicating that regular physical activity substantially reduces risk of type 2 diabetes. Adjustment for differences in body mass index between active and inactive groups attenuates the magnitude of risk reduction, but even after adjustment, a high level of physical activity is associated with a 20-30% reduction in diabetes risk. The data indicate that protection from diabetes can be conferred by a range of activities of moderate or vigorous intensity, and that regular light-intensity activity may also be sufficient, although the data for this are less consistent. The risk reduction associated with increased physical activity appears to be greatest in those at increased baseline risk of the disease, such as the obese, those with a positive family history and those with imp aired glucose regulation. Data from six large-scale diabetes prevention intervention trials in adults with impaired glucose tolerance or at high risk of cardiovascular disease indicate that increasing moderate physical activity by approximately 150 minutes per week reduces risk of progression to diabetes, with this effect being greater if accompanied by weight loss. However, this level of activity did not prevent all diabetes. with 2-13% of participants per annum who underwent lifestyle intervention still developing the disease. Thus, while 150 minutes per week of moderate activity confers benefits, higher levels of activity may be necessary to maximize diabetes risk reduction in those at high baseline risk of the disease. In contrast, those at low baseline risk of type 2 diabetes, e.g. people with a very low body mass index and no family history of diabetes, will remain at low risk of developing diabetes whether they are active or not. Thus, the amount of physical activity required to confer low risk of diabetes differs according to an individual's level of baseline risk. Consequently, a 'one size fits all' mass-population strategy may not provide the most appropriate approach when designing physical activity guidelines for the prevention of type 2 diabetes. Producing tailored guidelines with the specific aim of reducing risk of diabetes in high-risk populations may provide an alternative approac

Effect of 2 weeks of sprint interval training on health-related outcomes in sedentary overweight/obese men

The aim of this study was to investigate the effects of very high intensity sprint interval training (SIT) on metabolic and vascular risk factors in overweight/obese sedentary men. Ten men (age, 32.1 ± 8.7 years; body mass index, 31.0 ± 3.7 kg m-2) participated. After baseline metabolic, anthropometric, and fitness measurements, participants completed a 2-week SIT intervention, comprising 6 sessions of 4 to 6 repeats of 30-second Wingate anaerobic sprints on an electromagnetically braked cycle ergometer, with 4.5-minute recovery between each repetition. Metabolic, anthropometric, and fitness assessments were repeated post-intervention. Both maximal oxygen uptake (2.98 ± 0.15 vs 3.23 ± 0.14 L min-1, P = .013) and mean Wingate power (579 ± 24 vs 600 ± 19 W, P = .040) significantly increased after 2 weeks of SIT. Insulin sensitivity index (5.35 ± 0.72 vs 4.34 ± 0.72, P = .027) and resting fat oxidation rate in the fasted state (0.13 ± 0.01 vs 0.11 ± 0.01 g min-1, P = .019) were significantly higher and systolic blood pressure (121 ± 3 vs 127 ± 3 mm Hg, P = .020) and resting carbohydrate oxidation in the fasted state (0.03 ± 0.01 vs 0.08 ± 0.02 g min-1, P = .037) were significantly lower 24 hours post-intervention compared with baseline, but these changes were no longer significant 72 hours post-intervention. Significant decreases in waist (98.9 ± 3.1 vs 101.3 ± 2.7 cm, P = .004) and hip (109.8 ± 2.2 vs 110.9 ± 2.2 cm, P = .017) circumferences compared with baseline were also observed after the intervention. Thus, 2 weeks of SIT substantially improved a number of metabolic and vascular risk factors in overweight/obese sedentary men, highlighting the potential for this to provide an alternative exercise model for the improvement of vascular and metabolic health in this population

Postprandial lipemia: effects of intermittent versus continuous exercise

PURPOSE: The purpose of this study was to assess whether exercise performed in continuous and discontinuous formats reduced postprandial lipemia to a similar degree.<p></p> METHODS: Fifteen normolipidemic and three borderline hyperlipidemic healthy males (ages 30.6 +/- 9.0 (mean +/- SD) yr, BMI 23.1 +/- 1.4 kg.m-2) participated in three trials, each conducted over 2 d. Subjects refrained from exercise for the 2 d preceding each trial. On day one, subjects rested (control trial), or ran at 60% of maximal oxygen uptake in either one 90-min session (continuous exercise trial), or three 30-min sessions (intermittent exercise trial). On day two, subjects ingested a high-fat test breakfast (1.2 g fat, 1.2 g carbohydrate, 70 kJ energy per kilogram body mass). Blood samples were obtained in the fasted state and at intervals for 6 h postprandially.<p></p> RESULTS: Fasting plasma triacylglycerol (TAG) concentrations did not differ between trials. Areas under the TAG versus time curves were 18.1 +/- 6.7% (mean +/- SEM) and 17.7 +/- 7.6% (both P 0.05) lower than control in the continuous exercise and intermittent exercise trials, respectively. Plasma glucose responses to the test meal did not differ between trials, but the serum insulin response was lower in the intermittent exercise trial compared with that in the control.<p></p> CONCLUSION: The results suggest that both intermittent and continuous exercise can reduce postprandial lipemia.<p></p&gt