REM sleep and catecholamine excretion: a study in elite athletes

We investigated the potential influence of catecholamines on sleep architec ture in endurance-trained athletes. The hypothesis was that endogenous leve ls of aminergic neurotransmitters influence sleep architecture. Thirteen we ll-trained male street cyclists tall members of the German national amateur team, mean age 23.9 years, mean body mass index 21.9 kg/m(2)) completed th e protocol. Each subject was studied during training after a race competiti on (C) and later in a recovery/rest period (R) with no training and no comp etition. Polysomnography (PSG) was performed for one night (C) and for a se cond night some weeks later (R). Urinary levels of catecholamines collected during the preceding day and over the night of PSG were used as an index o f excretion rate of circulating adrenergic agonists. Nighttime and daytime excretion of epinephrine and norepinephrine was significantly elevated afte r exercise (C vs R: P<0.01). Rapid-eye-movement sleep (REM) onset latency w as significantly increased (P=0.03) and REM was significantly decreased in the first half of the night in the training compared to the resting conditi on (C vs R, P=0.05), REM latency was correlated with increased epinephrine excretion on the day of exercise (C, r=0.63, P=0.02). The temporal appearan ce of REM during the night appears to be affected in part by the intense ex ercise associated with race competition, and urinary catecholamines are mar kers that are correlated with this alteration in REM appearance.