Aerobic Exercise of 150 Minutes Weekly Significantly Reduces Body weight and body Fat, suggests JAMA study
Researchers have found that at least 150 minutes of aerobic exercise per week can help bring clinically significant reductions in body fat and waist circumference in adults with overweight or obesity. A recent study was conducted by Ahmad J. and colleagues which was published in the journal JAMA Network Open.
Data were retrieved from PubMed, Scopus, the Cochrane Central Register of Controlled Trials, and gray literature sources in the period of inception till April 2024. The randomized clinical trials selected were those of participants diagnosed with overweight or obesity for at least 8 weeks of supervised aerobic training.
The analysis followed the guidelines of the PRISMA, data extraction, and assessment were independent, and the two groups worked separately. Random-effects meta-analyses evaluated the effect of each 30-minute increase in weekly aerobic exercise on body weight, waist circumference, percentage body fat, and visceral and subcutaneous adipose tissues. The GRADE tool was used to grade the certainty of evidence.
Key Results
Body Weight Loss:
• Each 30 minutes of weekly aerobic exercise lowered body weight by 0.52 kg (95% CI, −0.61 to −0.44 kg; 109 trials, GRADE = moderate).
Waist Circumference Loss:
• The abdominal measurement narrowed down 0.56 cm per 30 minutes per week of exercise (95% CI, −0.67 to −0.45 cm; 62 trials, GRADE = high).
Percentage body fat:
• Body fat mass was decreased by 0.37% per 30 minutes per week of exercise (95% CI, −0.43% to −0.31%; 65 trials, GRADE = moderate).
Visceral and Subcutaneous Fat
• Visceral adipose tissue was reduced by 1.60 cm²(95% CI, −2.12 to −1.07 cm²; 26 trials, GRADE = high).
• Reduced subcutaneous adipose tissue: by 1.37 cm² (95% CI, −1.82 to −0.92 cm²; 27 trials; GRADE = moderate).
Quality of Life Improvements:
• Physical quality of life improved with standardized mean difference of 1.69 SD (95% CI, 1.18-2.20 SD).
• Mental quality of life modestly improved: standardized mean difference of 0.74 SD; 95% CI, 0.29-1.19 SD).
Adverse Events:
• Mild to moderate musculoskeletal symptoms were reported, with two extra events per 100 patients (95% CI, 1 to 2 more events; GRADE = low).
In conclusion, this meta-analysis underscores the effectiveness of aerobic exercise in reducing body weight, waist circumference, and body fat among individuals with overweight or obesity. Engaging in at least 150 minutes of moderate to vigorous aerobic training weekly can achieve clinically significant improvements, supporting its role as a cornerstone in obesity management strategies.
Reference:
Jayedi A, Soltani S, Emadi A, Zargar M, Najafi A. Aerobic Exercise and Weight Loss in Adults: A Systematic Review and Dose-Response Meta-Analysis. JAMA Netw Open. 2024;7(12):e2452185. doi:10.1001/jamanetworkopen.2024.52185
