Effects of Acute Exercise and Carbohydrate Intake on Plasma GDF-15 Levels and Its Association With Appetite Regulation.

Background: Growth differentiation factor 15 (GDF-15) is a potential therapeutic target for obesity due to its role in appetite suppression. Although acute exercise stimulates GDF-15 secretion, its relationship with appetite regulation remains unclear. It is also unknown whether preexercise carbohydrate intake would affect GDF-15 responses. This study aimed to examine the effects of acute exercise and carbohydrate intake on GDF-15 secretion and its potential links to appetite regulation.

Methods: In a secondary analysis of a randomized crossover trial, 12 healthy males completed four 120-minute trial conditions: (1) control (water) with rest, (2) control with exercise (0-30 minutes at ∼75% of maximal oxygen uptake), (3) carbohydrate (75 g maltodextrin) with rest, and (4) carbohydrate with exercise. Plasma GDF-15 levels were measured at 0, 30, 60, and 120 minutes, alongside subjective appetite ratings using visual analog scales. Energy intake was measured at the end of each trial condition with an ad libitum meal.

Results: Time-averaged area under the curve analysis showed that neither exercise [34 pg/mL (95% confidence interval [CI], -2-69 pg/mL); P = .062) nor carbohydrate intake [10 pg/mL (95% CI, -39-58 pg/mL); P = .673] independently or interactively (P = .283) affected GDF-15 levels. Exercise induced a delayed independent increase in GDF-15 at 120 minutes [55 pg/mL (95% CI, 18-94 pg/mL); P = .008]. No significant associations were found between GDF-15 levels and subjective appetite ratings or energy intake.

Conclusion: A 30-minute bout of high-intensity exercise induces a delayed increase in GDF-15 levels, which is not affected by carbohydrate intake. Physiological GDF-15 responses to acute exercise display no association with markers of appetite regulation.