Introduction: The aim of this research was to compare active and passive recovery after a session of intense exhaustive training on the level of serotonin in the serum of the runners.

Materials and Methods: In this semi-experimental study, 26 male elite runners were randomly assigned to two groups of active (n=12) and passive (n=14) recovery. Half an hour before the start of the training, 5 ml blood was drawn from the sample and then each subject was tested starting training on treadmill for Bruce test until reaching exhaustion. Immediately and then 10 minutes after the Bruce test, 5 ml of blood was drawn again for measuring serotonin.

Results and Conclusions:The mean of serotonin in three steps of before, immediately after and 10 minutes after recovery were respectively 360.83 ± 250.05, 459.67±302.13, 514.5±440.48 ng/ml in the active recovery group and 141.26 ± 92.41, 241.04 ± 104.78, 214.34 ± 120.03 ng/ml in the passive recovery group. There was a significant difference between the amount of serotonin after recovery compared to that of before. However, the type of recovery program after that had no effect on the serum serotonin of the blood of the runners