SHOULD FITNESS PROS ENCOURAGE CLIENTS TO LOSE WEIGHT
The benefits of exercise on cardiovascular disease markers are well established; however, there’s little evidence to determine whether these benefits are due to exercise, weight loss or a combination of both. To shed light on this, a recent study examined insulin sensitivity and cholesterol levels among exercisers who achieved either no weight loss (<3% reduction in body weight) or modest weight loss (≥3%).
The 163 volunteers (aged 52.4 ± 6.4 years) with overweight or obesity were randomized into three exercise groups or a nonexercise control: low amount, moderate intensity (LAMI); low amount, high intensity (LAHI); and high amount, high intensity (HAHI). Researchers tracked exercise amounts by measuring calories per kilogram per week (14 and 23 kcal/kg per week for LA and HA, respectively) and gauged intensity by measuring peak oxygen consumption (40%–55% and 65%–85% for moderate intensity and high intensity, respectively).
The HAHI exercise group had the highest percentage of modest and clinically significant weight loss (>5% reduction in body weight); however, this was not statistically significant compared with the other groups. Relative fitness level, reduction in triglycerides, non-HDL cholesterol and LDL particles were highest in those who achieved modest weight loss, independent of exercise group. All exercise groups improved insulin sensitivity, with the LAMI group showing the largest improvement.
While exercise is imperative for improving factors associated with CVD, the importance of achieving at least modest weight loss for clients with obesity or overweight should be shared.
REFERENCE: Swift, D.L., et al. 2018. Effects of aerobic training with and without weight loss on insulin sensitivity and lipids. PLOS ONE, 13 (5), e0196637.
TONY P. NUÑEZ, PHD,
is an assistant professor in exercise science at Metropolitan State University of Denver. He is an active researcher and presenter in the exercise physiology and fitness field.