Acute effect of exercise intensity on circulating FGF-21, FSTL-1, cathepsin B, and BDNF in young men
Minje Ji, Chaeeun Cho, Sewon Lee
Abstract
Exercise intensity is potentially an important regulator of various exerkines secretion, but the optimal exercise intensity to increase and sustain exerkines levels, including FGF-21, FSTL-1, cathepsin B, and BDNF in humans, has not yet been fully elucidated. This study aimed to examine the circulating levels of FGF-21, FSTL-1, cathepsin B, and BDNF according to the exercise intensity. Nine young men (24.0 ± 0.4 years old) performed 4 different experimental sessions at 1-week intervals: 1) a control session (CTRL; no exercise); 2) moderate-intensity continuous exercise (MICE, 55% HRR); 3) vigorous-intensity continuous exercise (VICE, 85% HRR); and 4) high-intensity interval exercise (HIIE, 4 repetitions of a 30-seconds of “all out” cycling workout followed by a 4-minute recovery). Blood samples were collected at 4 different time points (pre-exercise, immediately post-exercise, 30 min post-exercise, and 90 min post-exercise). Serum FGF-21, FSTL-1, cathepsin B, and BDNF were higher in HIIE than in CTRL immediately post-exercise, and FSTL-1, cathepsin B, and BDNF were higher in HIIE than in MICE immediately post-exercise (P < 0.05). The AUC for FGF-21, FSTL-1, and BDNF was higher in HIIE than in CTRL, and the AUC for FGF-21 and BDNF was higher in HIIE than in MICE (P < 0.05). Furthermore, the change in blood lactate was positively correlated with the changes in all exerkines. This study demonstrates that acute HIIE effectively increases serum FGF-21, FSTL-1, cathepsin B, and BDNF compared to MICE. Therefore, the secretion of exerkines, including FGF-21, FSTL-1, cathepsin B, and BDNF may be exercise intensity-dependent.