Relationships between leptin levels and carbohydrate intake during rowing training

Aim. This study was designed to determine the relationship between diet and leptin levels during rowing training. Methods. Dietary intakes using 3-day food records, training volume and leptin responses to a 90-min exercise (measurement before, at the end and after 2 and 24 h of recovery) were assessed at the beginning and at the end of an 8-month training season for heavyweight rowers. Results. During the training, we observed increases in energy intake and in training volume (12.1 +/- 1.8 and 14 +/- 1.4 MJ/day, and 3.8 +/- 1.1 and 6.5 +/- 1.8 sessions/week, respectively at the beginning and at the end of the season). Carbohydrate (CHO) and protein intakes were increased (P<0.001 and P<0.05, respectively), whereas those of lipid were unchanged (P=0.08). Leptin levels at rest were unchanged, while delayed decreases occurred (at 2 h postexercise) in response to the 90-min exercise (P<0.01). At the end of the season, postexercise and 24 h postexercise leptin levels were positively correlated to CHO intake (r=0.62 and r=0.69, respectively; P<0.05). Conclusion. There is an increase in CHO intake over a training season for rowers. Our results suggested that repeated hypoleptinemia in response to acute exercise triggered the particular choice of CHO in order to insure the energy homeostasis.