Exercise for Weight Loss: Further Evaluating Energy Compensation with Exercise

Abstract

Purpose This study assessed how individuals compensate for energy expended during a 12-wk aerobic exercise intervention, elucidating potential mechanisms and the role exercise dose plays in the compensatory response. Participants and Design Three-arm, randomized controlled trial among sedentary adults age 18 to 40 yr, body mass index of 25 to 35. Groups included six exercise sessions per week, two sessions per week, and sedentary control. Methods Rate of exercise energy expenditure was calculated from a graded exercise test averaged across five heart rate zones. Energy compensation was calculated as the difference between expected weight loss (based on exercise energy expenditure) and changes in fat and fat-free mass (DXA). Resting energy expenditure was assessed via indirect calorimetry and concentrations of acylated ghrelin, leptin, insulin, and Glucagon-like peptide 1 (GLP-1) were assessed fasting and postprandial (six timepoints over 2 h). Results The 6-d·wk −1 group expended more energy (2753.5 kcal) and exercised longer (320.5 min) per week than the 2-d·wk −1 group (1490.7 kcal, 1888.8 min, P < 0.05), resulting in greater fat loss compared with the 2-d or control groups ( P < 0.05). Exercise groups did not differ in the % or total kcal compensated. Greater decreases in area under the curve (AUC) for acylated ghrelin predicted greater fat loss, regardless of group, energy expended per week, exercise duration, or exercise intensity. Changes in leptin AUC was the only independent predictor for energy compensation, with a greater decrease in leptin AUC predicting less energy compensation. Exercise frequency, energy expended, duration, or intensity did not influence energy compensation. Conclusions Leptin is an important factor in successful weight loss through exercise, with greater postprandial decreases promoting less compensation. Greater amounts of exercise do not influence the compensatory response to an exercise-induced energy deficit.

Reactive Oxygen Species (ROS) and Antioxidants as Immunomodulators in Exercise: Implications for Heme Oxygenase and Bilirubin

“…By comparing changes in bodily energy stores with the amount of total energy expended through exercise, we have demonstrated this compensatory response to equate to roughly 1000 kcal per week during a 12-week exercise intervention, and that energy expenditures of greater than 2700 kcal per week are needed to achieve significant weight loss after 12 weeks. [ 28 , 29 ]. Others have reported that greater amounts of exercise can evoke a proportionally greater compensatory response [ 30 ], potentially explaining why exercise interventions with large differences in daily and weekly exercise energy expenditures can promote similar weight loss [ 30 , 31 , 32 , 33 ].…”

The Mystery of Energy Compensation

“…I find very limited evidence in the human literature of BMR decreasing in response to a chronic period of increased activity energy expenditure per se. In most studies where participants exhibited no change or only a marginal decrease in body mass in response to an increase in daily activity levels they also exhibited no change in BMR (often calculated independent of body condition) (Colley 2008;Colley et al 2010;Flack et al 2020;Goran and Poehlman 1992;Hand et al 2020;Herrmann et al 2015;Meijer et al 1999;Riou et al 2019;Van Etten et al 1997;Willis et al 2014). In a few studies where participants experienced no change in body mass they exhibited a small increase in BMR (Hunter et al 2000;Morio et al 1998;Withers et al 1998).…”

Exercise and Nutritional Strategies to Promote Weight Loss: A Narrative Review

“…Low to moderate intensity exercise provides significant health benefit but marginally affects weight loss in sedentary individuals initiating training. Diet intervention serves as the primary means of initially promoting weight loss in sedentary overweight or obese individuals but greater and more sustained effects are observed when combining diet and exercise [75]. Low to moderate intensity cardiovascular exercise has been the most common form of physical activity in weight loss studies.…”