Scientists from Iran (Mozezzaneh. 2010) have now found that 5g of supplemental l-arginine significantly decreased the blood lactate levels of athletes (N=30) in the course of a 3 week supplementation period, but failed to induce consecutive or concurrent increases in VO2 max (a direct marker of exercise capacity):
Blood lactate level was significantly decreased in the L-arginine group compared to the placebo one. There was no significant difference between the two groups in VO2max at anaerobic threshold. Only in the L-arginine group, VO2 max at anaerobic threshold was significantly increased. In addition, there was no significant difference in VO2 max at anaerobic threshold for the placebo group.If you remember the previous news on arginine, you may understand that I will repeat my advice not to flush your good old pre-workout down the toilet. Even if it was just for the cosmetic pump and the decrease in lactic acid, this is probably more than some newer and probably fancier products will provide.