Aerobic Plus Resistance Exercise in Obese Older Adults Improves Muscle Protein Synthesis and Preserves Myocellular Quality Despite Weight Loss

Anabolic resistance and impaired myocellular quality contribute to age-related sarcopenia, which exacerbates with obesity. Diet-induced muscle mass loss is attenuated by resistance or aerobic plus resistance exercise compared to aerobic exercise in obese elderly. We assessed chronic effects of weight loss plus different exercise modalities on muscle protein synthesis response to feeding and myocellular quality. Obese older adults were randomized to a weight-management program plus aerobic, resistance, or combined aerobic and resistance exercise or to control. Participants underwent vastus lateralis biopsies at baseline and 6 months. Muscle protein synthesis rate increased more in resistance and combined than in control. Autophagy mediators’ expression decreased more in combined than in aerobic, which experienced a higher increase in inflammation and mitochondrial regulators’ expression. In obese elderly, combined aerobic and resistance exercise is superior to either mode independently for improving muscle protein synthesis and myocellular quality, thereby maintaining muscle mass during weight-loss therapy. Anabolic resistance and impaired myocellular quality contribute to age-related sarcopenia, which worsens with obesity. However, weight-loss programs can exacerbate sarcopenia. Colleluori et al. show that during weight-loss therapy, aerobic plus resistance exercise is more effective than aerobic or resistance exercise alone in improving muscle protein synthesis and myocellular quality, thereby preserving muscle mass in dieting, obese older adults.