Summary: This systematic review examined the effect of exercise training interventions on physical fitness in adults with overweight or obesity and compared the effectiveness of different types of exercise training. Four electronic databases were searched. Articles were included if they described randomized controlled trials of exercise training interventions and their effect on maximal oxygen consumption or muscle strength in adults with overweight or obesity. Changes in outcome parameters were analyzed using random effects meta‐analyses for different training types (aerobic, resistance, combined aerobic plus resistance, and high‐intensity interval training). Eighty‐eight articles satisfied the inclusion criteria of which 66 (3964 participants) could be included in the meta‐analyses. All training types increased VO_2max (mean difference 3.82 ml/min/kg (95% CI 3.17, 4.48), P < 0.00001; I² = 48%). In direct comparisons, resistance training was less effective in improving VO_2max than aerobic training, HIIT was slightly more effective than aerobic training, and no difference between aerobic and combined aerobic plus resistance training was found. For muscle strength benefits, incorporation of resistance exercise in the training program is indicated. Exercise training increases VO_2max and muscle strength in adults with overweight or obesity. Differences between training types should be weighed with other needs and preferences when health professionals advise on exercise training to improve physical fitness.

Summary: We aimed to assess the effectiveness of exercise training programs in adults with severe obesity undergoing bariatric surgery. A systematic search of controlled trials published up to October 2019 that assigned participants to either a preoperative or postoperative exercise training group or a nonexercise group was performed. Meta‐analyses were conducted using random‐effects models. Twenty‐two training programs were assessed (18 performed after bariatric surgery). The effect of preoperative exercise training on postsurgery outcomes was reported in only one study. Compared with the control condition without exercise, postoperative exercise training led to higher weight loss (N = 14, mean difference [95% CI] = −1.8 [−3.2; −0.4] kg,P = 0.01), fat loss (N = 9,P = 0.01), increase in VO₂max (N = 8,P < 0.0001), and increase in muscle strength (N = 9,P < 0.0001). No significant effect was found on lean body mass (N = 11). Preliminary evidence suggests a beneficial effect of postoperative exercise training on bone mineral density (N = 3,P < 0.001) and weight maintenance after the end of the intervention (N = 2,P < 0.001) but no significant effect on quality of life (N = 2), habitual physical activity (N = 2), or cardiometabolic outcomes (N < 4). In conclusion, exercise training performed after bariatric surgery improves physical fitness and leads to a small additional weight and fat loss and may prevent bone loss and weight regain after bariatric surgery.

Summary: This systematic review examined the impact of exercise intervention programs on selected cardiometabolic health indicators in adults with overweight or obesity. Three electronic databases were explored for randomized controlled trials (RCTs) that included adults with overweight or obesity and provided exercise‐training interventions. Effects on blood pressure, insulin resistance (homeostasis model of insulin resistance, HOMA‐IR), and magnetic resonance measures of intrahepatic fat in exercise versus control groups were analyzed using random effects meta‐analyses. Fifty‐four articles matched inclusion criteria. Exercise training reduced systolic and diastolic blood pressure (mean difference, MD = −2.95 mmHg [95% CI −4.22, −1.68], p < 0.00001, I² = 63% and MD = −1.93 mmHg [95% CI −2.73, −1.13], p < 0.00001, I² = 54%, 60 and 58 study arms, respectively). Systolic and diastolic blood pressure decreased also when considering only subjects with hypertension. Exercise training significantly decreased HOMA‐IR (standardized mean difference, SMD = −0.34 [−0.49, −0.18], p < 0.0001, I² = 48%, 37 study arms), with higher effect size in subgroup of patients with type 2 diabetes (SMD = −0.50 [95% CI: −0.83, −0.17], p = 0.003, I² = 39%). Intrahepatic fat decreased significantly after exercise interventions (SMD = −0.59 [95% CI: −0.78, −0.41], p < 0.00001, I² = 0%), with a larger effect size after high‐intensity interval training. In conclusion, exercise training is effective in improving cardiometabolic health in adults with overweight or obesity also when living with comorbitidies.

Summary: This systematic review examined the impact of exercise training interventions on energy intake (EI) and appetite control in adults with overweight/obesity (≥18 years including older adults). Articles were searched up to October 2019. Changes in EI, fasting appetite sensations, and eating behavior traits were examined with random effects meta‐analysis, and other outcomes were synthesized qualitatively. Forty‐eight articles were included (median [range] BMI = 30.6 [27.0–38.4] kg/m²). Study quality was rated as poor, fair, and good in 39, seven, and two studies, respectively. Daily EI was assessed objectively (N = 4), by self‐report (N = 22), with a combination of the two (N = 4) or calculated from doubly labeled water (N = 1). In studies rated fair/good, no significant changes in pre‐post daily EI were found and a small but negligible (SMD < 0.20) postintervention difference when compared with no‐exercise control groups was observed (five study arms; MD = 102 [1, 203] kcal). There were negligible‐to‐small pre‐post increases in fasting hunger and dietary restraint, decrease in disinhibition, and some positive changes in satiety and food reward/preferences. Within the limitations imposed by the quality of the included studies, exercise training (median duration of 12 weeks) leads to a small increase in fasting hunger and a small change in average EI only in studies rated fair/good. Exercise training may also reduce the susceptibility to overconsumption (PROSPERO: CRD42019157823).

BACKGROUND Vitamin D has been suggested to affect peripheral insulin sensitivity. Evidence regarding the effect of vitamin D supplementation on insulin sensitivity is still conflicting. PURPOSE This meta-analysis aimed to assess the effect of vitamin D supplementation on insulin sensitivity in humans with or at risk for insulin resistance. DATA SOURCES AND STUDY SELECTION PubMed, Web of Science, Embase, CINAHL, and Cochrane Library were systematically searched for randomized controlled trials (RCTs) from 1980 until 31 December 2018 reporting treatment effects of vitamin D supplementation on insulin sensitivity. DATA EXTRACTION The main outcome of interest was the change in insulin sensitivity, derived from the gold standard hyperinsulinemic-euglycemic clamp or the Matsuda index derived from the oral glucose tolerance test and insulin sensitivity index from intravenous glucose tolerance test. We extracted data on the standardized mean difference between the vitamin D treatment and placebo groups in change from baseline insulin sensitivity. DATA SYNTHESIS Eighteen RCTs were included in this meta-analysis comparing vitamin D supplementation (n = 612) with placebo (n = 608). Vitamin D supplementation had no effect on insulin sensitivity (standardized mean difference −0.01, 95% CI −0.12, 0.10; P = 0.87, I² = 0%). Visual inspection of funnel plot symmetry did not suggest potential publication bias. LIMITATIONS The number of individuals who participated in the included studies was relatively small, possibly due to the invasive character of the measurement (e.g., clamp). CONCLUSIONS This meta-analysis provides no evidence that vitamin D supplementation has a beneficial effect on peripheral insulin sensitivity in people with or at risk for insulin resistance.