Search

Aerobic exercise is recommended for weight management but energy balance is often less negative than predicted from exercise energy expenditure (ExEE). To examine effects of active commuting and leisure-time exercise on fat loss in women and men with overweight and obesity. We randomized 130 younger, physically inactive women and men with overweight and obesity (body mass index: 25–35 kg m−2) to 6 months of habitual lifestyle (control; CON, n=18), active commuting (BIKE, n=35) or leisure-time exercise of moderate (MOD, 50% VO2peak reserve, n=39) or vigorous intensity (VIG, 70% VO2peak reserve, n=38). The primary outcome was change in fat mass measured by dual-energy X-ray absorptiometry, which was analyzed intention-to-treat. Accumulated energy balance was calculated based on changes in body composition, and ExEE was calculated based on heart rate monitoring during exercise. Testing at 3 and 6 months was completed by 95 and 90 participants, respectively. Fat mass was reduced after 3 and 6 months in BIKE (3 months: −3.6 (−5.5; −1.7) kg (mean (95% CI)); 6 months: −4.2 (−6.6; −1.9) kg; both: P

Regular physical activity is efficacious for improving metabolic health in overweight and obese individuals, yet, many adults lead sedentary lives. Most exercise interventions have targeted leisure time, but physical activity also takes place in other domains of everyday life. Active commuting represents a promising alternative to increase physical activity, but it has yet to be established whether active commuting conveys health benefits on par with leisure time physical activity (LTPA). A 6-month randomized controlled trial was designed to investigate the effects of increased physical activity in transport (bicycling) or leisure time domains (moderate or vigorous intensity endurance exercise). We included 188 overweight and class 1 obese sedentary women and men (20–45 years) of which 130 were randomized to either sedentary controls ( n = 18), active commuting ( n = 35) or moderate ( n = 39) or vigorous ( n = 38) intensity LTPA. At baseline and after 3 and 6 months, participants underwent a rigorous 3-day biomedical test regimen followed by free-living measurements. In a sub-sample, physical activity level and energy expenditure were monitored by means of personal assistive technology and the doubly labeled water technique. Additionally, the delivery, reception and routinization of the exercise regimens were investigated by ethnological fieldwork. One year after termination of the intervention, participants will be invited for a follow-up visit to investigate sustained health effects and continuous physical activity adherence. By combining biomedical, technological and humanistic approaches, we aim to understand the health benefits of physical activity in different domains of everyday life, as well as how to improve adherence to physical activity.

Physical exercise increases peripheral insulin sensitivity, but regional differences are poorly elucidated in humans. We investigated the effect of aerobic exercise training on insulin-stimulated glucose uptake in five individual femoral muscle groups and four different adipose tissue regions, using dynamic (femoral region) and static (abdominal region) 2-deoxy-2-[18F]fluoro-d-glucose (FDG) PET/CT methodology during steady-state insulin infusion (40 mU·m−2·min−1). Body composition was measured by dual X-ray absorptiometry and MRI. Sixty-one healthy, sedentary [V̇o2max 36(5) ml·kg−1·min−1; mean(SD)], moderately overweight [BMI 28.1(1.8) kg/m2], young [age: 30(6) yr] men were randomized to sedentary living (CON; n = 17 completers) or moderate (MOD; 300 kcal/day, n = 18) or high (HIGH; 600 kcal/day, n = 18) dose physical exercise for 11 wk. At baseline, insulin-stimulated glucose uptake was highest in femoral skeletal muscle followed by intraperitoneal visceral adipose tissue (VAT), retroperitoneal VAT, abdominal (anterior + posterior) subcutaneous adipose tissue (SAT), and femoral SAT ( P < 0.0001 between tissues). Metabolic rate of glucose increased similarly (∼30%) in the two exercise groups in femoral skeletal muscle (MOD 24[9, 39] μmol·kg−1·min−1, P = 0.004; HIGH 22[9, 35] μmol·kg−1·min−1, P = 0.003) (mean[95% CI]) and in five individual femoral muscle groups but not in femoral SAT. Standardized uptake value of FDG decreased ∼24% in anterior abdominal SAT and ∼20% in posterior abdominal SAT compared with CON but not in either intra- or retroperitoneal VAT. Total adipose tissue mass decreased in both exercise groups, and the decrease was distributed equally among subcutaneous and intra-abdominal depots. In conclusion, aerobic exercise training increases insulin-stimulated glucose uptake in skeletal muscle but not in adipose tissue, which demonstrates some interregional differences.

BACKGROUND AND AIMS: Physical inactivity is linked to low-grade inflammation, endothelial dysfunction and cardiovascular disease. We aimed to determine effects of active commuting and leisure time exercise on markers of low-grade inflammation and endothelial function in overweight and obese women and men.METHODS: We randomized 130 younger (20-45 years), physically inactive, healthy, overweight and obese (BMI: 25-35 kg/m(2)) women and men recruited from the Copenhagen area, Denmark, to either 6 months of habitual lifestyle (CON, n = 18), active commuting (BIKE, n = 35), or leisure time exercise of moderate (MOD, ∼50% VO2peak, n = 39) or vigorous intensity (VIG, ∼70% VO2peak, n = 38). Fasting blood samples were collected at baseline, 3, and 6 months and analyzed for concentrations of C-reactive protein (CRP), fibrinogen, von Willebrand factor (vWF), tissue-type plasminogen activator (t-PA), and plasminogen activator inhibitor type 1 (PAI-1), and 90 participants (CON, n = 16; BIKE, n = 19; MOD, n = 31, VIG, n = 24) were included in a per-protocol analysis.RESULTS: We observed lower concentrations of CRP in MOD compared with CON at 6 months (p = 0.013) and within-group decreases in CRP in BIKE (3 months: p = 0.045) and MOD (3 months: p = 0.061; 6 months: p = 0.038) corresponding to a 30% decrease in BIKE and 19% in MOD from baseline till 6 months. No effects of exercise were observed on fibrinogen, vWF, t-PA, PAI-1 or the t-PA/PAI-1 ratio within or between groups.CONCLUSIONS: Our findings suggest an anti-inflammatory effect of active commuting and moderate, but not vigorous, intensity leisure time exercise, but no alterations in endothelial function during 6 months of intervention.