L-Arginine Reduces Exercise-Induced Increase in Plasma Lactate and Ammonia

Abstract

To investigate the effect of L-arginine supplementation (L-ARG) on physiological and metabolic changes during exercise, we determined in a double-blind study the cardiorespiratory (heart rate, oxygen consumption (VO(2)) and carbon dioxide production (VCO(2)) and the metabolic (lactate and ammonia) responses to maximal exercise after either an intravenous L-ARG hydrochloride salt or placebo load in 8 healthy subjects. Exercise-induced increases in heart rate, VO(2) and VCO(2) were not significantly different after L-ARG or placebo. By contrast, peak plasma ammonia and lactate were significantly decreased after L-ARG load (60.6 +/- 8.2 vs. 73.1 +/- 9.1 micro mol x l(-1), p < 0.01 and 7.1 +/- 0.7 vs. 8.2 +/- 1.1 mmol x l(-1), p < 0.01, for ammonia and lactate, respectively). Plasma L-citrulline increased significantly during exercise only after L-ARG load, despite a concomitant decrease in plasma L-ARG. Furthermore, a significant inverse relationship was observed between changes in lactate and L-citrulline concentrations after L-ARG load (r = -0.84, p = 0.009). These results demonstrate that intravenous L-ARG reduces significantly exercise-induced increase in plasma lactate and ammonia. Taken together, the specific L-citrulline increase and the inverse relationship observed between L-citrulline and plasma lactate after L-ARG might support that L-ARG supplementation enhances the L-arginine-nitric oxide (NO) pathway during exercise.

Low-dose l -arginine administration increases microperfusion of hindlimb muscle without affecting blood pressure in rats

“…Accordingly, one question that can be raised is whether the vasodilation at rest caused by L-arginine can improve exercise capacity. L-Arginine has already been reported to be useful in reducing exercise-induced increases in plasma lactate and ammonia (54). Improved muscle blood flow after L-arginine administration can explain the reduction in muscle and plasma lactate and ammonia levels.…”

Two weeks of watermelon juice supplementation improves nitric oxide bioavailability but not endurance exercise performance in humans

“…The most recognised pathway for nitric oxide generation is the oxidation of L-arginine catalysed by the nitric oxide synthase enzymes to yield nitric oxide and L-citrulline [3]. However, while oral L-arginine supplementation can increase circulating [L-arginine] [4,5], and therefore one of the substrates for nitric oxide synthase, whether oral Larginine supplementation increases nitric oxide biomarkers (nitrate and nitrite) and improves exercise performance is controversial [4,[6][7][8][9], see 10 for review]. These conflicting findings might be linked, at least in part, to significant pre-systemic [11,12] and systemic [11,[13][14][15][16] breakdown of orally ingested L-arginine.…”

l-Citrulline supplementation improves O2 uptake kinetics and high-intensity exercise performance in humans

“…1 for review). However, when Arg treatment increases NO biomarkers, exercise economy and exercise performance are improved (5,52), whereas exercise economy and exercise performance are not improved when Arg treatment does not influence NO synthesis (9,31,35,60). Therefore, while there is some evidence to suggest that Arg treatment might improve physiological responses in conjunction with elevated NO synthesis, an optimal Arg administration procedure to enhance NO synthesis and associated physiological responses has yet to be established.…”