Physical activity reduces waist circumference.
Waist circumference is an indicator of abdominal body fat, which is associated with cardiometabolic disease, which in turn is predictive of mortality. A 1cm increase in waist circumference may increase the relative risk of cardiovascular events by 2%(1).
Several meta-analyses were identified that investigated the effect of exercise on waist circumference.
A network meta-analysis of 45 studies with a total of 3566 participants of an average age of 43.3 and a BMI over 30 showed results consistent with a strong effect of exercise on waist circumference. Aerobic exercise was effective, but the most effective interventions included some degree of resistance training as well, with a reduction in waist circumference of −2.76cm (−4.52, −1.00)(2)
A meta-analysis that investigated the effects of exercise in addition to diet on waist circumference. 8 studies with 1124 participants compared diet to diet and exercise and found a mean difference of -1.68 cm (95% CI -2.66 to -0.70). Diet may be more important however as the effect of adding diet to exercise lead to a mean difference between diet and exercise versus exercise alone of -3.00 cm (95% CI -5.81 to -0.20). A direct comparison between exercise and diet alone however did not reveal any difference(3)
In a meta-analysis by Kim et al, the effect of exercise interventions on waist circumference was analysed across 3516 adults. The average size of effects that exercise interventions had on waist circumferences without dietary intervention was medium 0.562 (0.333 to 0.792) (4). Across all studies within the meta-analysis, exercise intervention time was 16.5 weeks with an average time of 153.3 minutes per week of different intensity.
Quality of evidence
A: Consistent evidence from meta-analysis and systematic review
Strength of recommendation
1 – Small, but significant benefit, low risk of physical activity
Conclusion
Exercise, particularly aerobic and combination training, may reduce waist circumference in overweight and obese individuals. The effect is improved with diet control. Waist circumference reduction is crucial in reducing risk of cardiovascular disease as it is a surrogate marker for abdominal and visceral adiposity. All patients who are overweight or obese should engage in exercise to reduce their cardiovascular risk.
1. Powell-Wiley TM, Poirier P, Burke LE, Després J-P, Gordon-Larsen P, Lavie CJ, et al. Obesity and Cardiovascular Disease: A Scientific Statement From the American Heart Association. Circulation. 2021 May;143(21):e984–1010.
2. O’Donoghue G, Blake C, Cunningham C, Lennon O, Perrotta C. What exercise prescription is optimal to improve body composition and cardiorespiratory fitness in adults living with obesity? A network meta-analysis. Obes Rev an Off J Int Assoc Study Obes. 2021 Feb;22(2):e13137.
3. Schwingshackl L, Dias S, Hoffmann G. Impact of long-term lifestyle programmes on weight loss and cardiovascular risk factors in overweight/obese participants: a systematic review and network meta-analysis. Syst Rev. 2014 Oct;3:130.
4. Kim K-B, Kim K, Kim C, Kang S-J, Kim HJ, Yoon S, et al. Effects of Exercise on the Body Composition and Lipid Profile of Individuals with Obesity: A Systematic Review and Meta-Analysis. J Obes Metab Syndr. 2019 Dec;28(4):278–94.