Endocrine and neuromodulatory regulation during prolonged maximal 6000-m rowing in male athletes

PURPOSE: The 6000-m rowing ergometer test represents a prolonged maximal effort commonly used in elite rowing; however, its physiological responses are less well characterized than those observed during the standard 2000-m race-distance format. This study aimed to examine acute endocrine and neuromodulatory responses to a maximal 6000-m rowing test in elite male rowers. METHODS: Nineteen elite male rowers performed a maximal 6000-m rowing ergometer test. Venous blood samples were collected before exercise (PRE), immediately after exercise (POST), and after 1 h of recovery (1-h REC). Serum concentrations of cortisol, testosterone, serotonin, dopamine, β-endorphin, anandamide, and 2-arachidonoylglycerol were determined. Testosterone-to-cortisol and serotonin-to-dopamine ratios were calculated. Achievement motivation was assessed before exercise to describe task engagement. RESULTS: Cortisol concentrations did not change across time points. Testosterone decreased at POST and increased above baseline at 1-h REC, resulting in corresponding changes in the testosterone-to-cortisol ratio. Serotonin concentrations decreased after exercise and remained reduced during recovery, whereas dopamine increased at POST and remained elevated at 1-h REC, leading to a reduced serotonin-to-dopamine ratio. β-Endorphin increased after exercise and remained elevated during recovery. Anandamide concentrations did not change significantly, while 2-arachidonoylglycerol showed a transient post-exercise decrease. Achievement motivation was not associated with acute physiological responses. CONCLUSION: Prolonged maximal rowing induced a physiological response characterized by distinct temporal patterns of endocrine and peripheral neuromodulatory markers during early recovery. These responses differ from those typically observed during race-distance testing and may contribute to the characterization of early post-exercise responses following prolonged maximal rowing exercise.