|Science is still wrestling with evidence in favor vs. against l-arginine|
Aside from the dosage, which would be on the higher side compared to the average arginine trial, there were no significant differences to study protocols you know.
The subjects reported to the laboratory fasted in the AM, they have followed identical diets before both the active and the placebo trial and they had to perform one of those arduous pedal until you drop exercise tests on a cycle ergometer...
There was one difference, however. The subjects were not allowed to start working out immediately after they'd washed down the arginine / placebo supplement. Instead, they had to wait for sixty minutes for the arginine peak in plasma (Gannon. 2002).
|Figure 1: Time to exhaustion and lactate levels increased, the VO2 costs of which you could expect that they decreased and would thus allow for the increased time to exhaustion, on the other hand, didn't change (Yavuz. 2014)|
In that, it is quite astonishing that these improvements occurred in the absence of changes in VO2 consumption. A reduction in O2 cost, as it was reported by Bailey et al. (2009) would after all be the most obvious explanation of the ergogenic effects of arginine.
- Bailey, Stephen J., et al. "Dietary nitrate supplementation reduces the O2 cost of low-intensity exercise and enhances tolerance to high-intensity exercise in humans." Journal of Applied Physiology 107.4 (2009): 1144-1155.
- Gannon, Mary C., Jennifer A. Nuttall, and Frank Q. Nuttall. "Oral arginine does not stimulate an increase in insulin concentration but delays glucose disposal." The American journal of clinical nutrition 76.5 (2002): 1016-1022.
- Yavuz, H. U., H. Turnagol, and A. H. Demirel. "PRE-EXERCISE ARGININE SUPPLEMENTATION INCREASES TIME TO EXHAUSTION IN ELITE MALE WRESTLERS." Biol. Sport 31 (2014): 187-191.