Effect of fat free mass on serum and plasma BDNF concentrations during exercise and recovery in healthy young men.

Exercise results in release of brain derived neurotrophic factor into the circulation; however, little is known about the changes in serum and plasma brain derived neurotrophic factor concentrations and factors influencing brain derived neurotrophic factor during exercise and recovery. Serum (n=23) and plasma (n=10) brain derived neurotrophic factor concentrations were measured in healthy young men at rest, during steady-rate and after exercise to determine the maximum aerobic power. A two-way analysis of variance was used to investigate brain derived neurotrophic factor levels in blood during exercise and recovery, with one between-subject factor (a median split on: age, height, body mass, fat free mass, body mass index and aerobic fitness), and one within-subject factor (time). Serum brain derived neurotrophic factor concentrations increased in response to exercise and declined rapidly in recovery. Plasma brain derived neurotrophic factor had a greater proportional increase relative to exhaustive exercise compared with serum brain derived neurotrophic factor and was slower to return to near baseline values. There was a significant group-by-time interaction indicating a greater release and faster recovery for serum brain derived neurotrophic factor in high- compared with low-fat free mass individuals.