Background: The aim of this study was to investigate the response of the most important angiogenic and angiostatic factors to a session activity before and after a period of L-Arginine supplementation in active men.

Materials and Methods: In this practical and semi experimental study, 22 active men were selected by convenience sampling method and they were randomly assigned into supplement (n=11) and placebo (n=11) groups. Baseline levels of VEGF and endostatin were measured, then subjects participated an exhaustive treadmill protocol in pre-test and post-test. Immediately and two hours after the protocol, 3 cc blood samples were prepared. The subjects used daily 0.1 g.kg^-1 respectively taking l-arginine and placebo for 14 days. The results were analyzed at the significant level (p<0.05).

Results: Immediately after exercise, the levels of VEGF and VEGF to endostatin ratio were significantly decreased in both groups compared to baseline (p≤0.05), and two hours later this change were lower than the baseline value (p≤0.05). The levels of endostatin immediately after exercise were significantly increased in both groups compared to baseline (p≤0.05) and two hours later this change were lower than the baseline value (p≤0.05). Before and after L-Arginine supplementation, the levels, of VEGF and VEGF to endostatin ratio immediately after exercise were not significant(p≥0.05). while this change in the supplementation group were significantly increased two hours after exercise (p≤0.05). There was no significant change in the levels of endostatin between two groups immediately after exercise (p≥0.05); however, these changes were significantly decreased two hours after exercise (p≤0.05).

Conclusion: It seems that short-term L-arginine supplementation probably stimulate angiogenesis factors in response to exercise in active men.