Article

Effects of 7 days of arginine-alpha-ketoglutarate supplementation on blod flow, plama L-arginine, nitric oxide metabolites, and asymmetric dimethyl arginine after resistance exercise

Dept. of Health, Human Performance, and Recreation, Baylor University, Waco, TX, USA.
International Journal of Sport Nutrition and Exercise Metabolism (Impact Factor: 1.98). 08/2011; 21(4):291-9.
Source: PubMed

ABSTRACT Arginine-alpha-ketoglutarate (AAKG) supplements are alleged to increase nitric oxide production, thereby resulting in vasodilation during resistance exercise. This study sought to determine the effects of AAKG supplementation on hemodynamics and brachial-artery blood flow and the circulating levels of L-arginine, nitric oxide metabolites (NOx; nitrate/nitrite), asymmetric dimethyl arginine (ADMA), and L-arginine:ADMA ratio after resistance exercise.
Twenty-four physically active men underwent 7 days of AAKG supplementation with 12 g/day of either NO(2) Platinum or placebo (PLC). Before and after supplementation, a resistance-exercise session involving the elbow flexors was performed involving 3 sets of 15 repetitions with 70-75% of 1-repetition maximum. Data were collected immediately before, immediately after (PST), and 30 min after (30PST) each exercise session. Data were analyzed with factorial ANOVA (p < .05).
Heart rate, blood pressure, and blood flow were increased in both groups at PST (p = .001) but not different between groups. Plasma L-arginine was increased in the NO(2) group (p = .001). NOx was shown to increase in both groups at PST (p = .001) and at 30PST (p = .001) but was not different between groups. ADMA was not affected between tests (p = .26) or time points (p = .31); however, the L-arginine:ADMA ratio was increased in the NO(2) group (p = .03).
NO(2) Platinum increased plasma L-arginine levels; however, the effects observed in hemodynamics, brachial-artery blood flow, and NOx can only be attributed to the resistance exercise.

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    • "However, high intravenous doses (~30 g) of another metabolic nitric oxide intermediate, larginine , have been shown to cause vasodilation (Willoughby, et al. 2011). With this in mind, our study was done in order to determine whether or not A-AKG stimulated significant nitric oxide production when individuals were given the recommended dose of the NO supplement. "
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