Arginine Supplementation For Endurance and Intensity

A few days ago, my collegues from the Dutch version of Ergo-Log reported on an older study (Esporte. 2007) which showed improvements in strength in a group of subjects supplemented with 3g of arginine per day. Now, a more recent study by Bailey et al. (Bailey. 2010) investigated the effect of 6g arginine mixed in a beverage that was consumed 1 hour before the completion of "a series of 'step' moderate-intensity and severe-intensity exercise bouts". The scientists found that...

Figure 1: Chemical structure
of l-Arginine (HMBD v2.5)

Plasma [nitrite] was significantly greater following L-arginine consumption compared to placebo (ARG: 331 ± 198 vs. PLA: 159 ± 102 nM; P<0.05) and systolic blood pressure was significantly reduced (ARG: 123 ± 3 vs. PLA: 131 ± 5 mmHg; P<0.01). The steady-state VO2 during moderate-intensity exercise was reduced by 7% in the ARG condition (ARG: 1.48 ± 0.12 vs. PLA: 1.59 ± 0.14 L /min; P<0.05). During severe-intensity exercise, the VO2 slow component amplitude was reduced (ARG: 0.58 ± 0.23 vs. PLA: 0.76 ± 0.29 L/min; P<0.05) and the time-to-exhaustion was extended (ARG: 707 ± 232 s vs. PLA: 562 ± 145 s; P<0.05) following ARG.

According to the authors' conclusion the effect of the increased availability of  nitrite that is accompanied by an elevation in bioavailability NO reduced the O2 cost of moderate-intensity exercise, which in turn extended the time-to-exhaustion during severe-intensity exercise.

If this is no reason not to dump your good old "1st generation"-preworkout products (e.g. NO Xplode, White Flood, Super Pump 250, VPX Shotgun), the main working ingredient of which is - guess what: Arginine.