Bolus Arginine Supplementation Affects neither Blood Flow nor Protein Synthesis

[THEHUGE]

Bolus Arginine Supplementation Affects neither Muscle Blood Flow nor Muscle Protein Synthesis in Young Men at Rest or After Resistance Exercise.
Tang JE, Lysecki PJ, Manolakos JJ, Macdonald MJ, Tarnopolsky MA, Phillips SM.

Department of Kinesiology, Exercise Metabolism Research Group and.

Abstract
The aim of this study was to investigate the ergogenic potential of arginine on NO synthesis, muscle blood flow, and skeletal muscle protein synthesis (MPS). Eight healthy young men (22.1 ± 2.6 y, 1.79 ± 0.06 m, 76.6 ± 6.2 kg; mean ± SD) participated in 2 trials where they performed a bout of unilateral leg resistance exercise and ingested a drink containing either 10 g essential amino acids with 10 g l-arginine (ARG) or an isonitrogenous control (CON). Femoral artery blood flow of both the nonexercised and exercised leg was measured continuously using pulsed-wave Doppler ultrasound, while rates of mixed and myofibrillar MPS were determined using a primed continuous infusion of l-[ring-(13)C(6)] or l-[ring-(2)H(5)]phenylalanine. The plasma arginine concentration increased 300% during the ARG trial but not during the CON trial (P < 0.001). Plasma nitrate, nitrite, and endothelin-1, all markers of NO synthesis, did not change during either the ARG or CON trial. Plasma growth hormone increased to a greater degree after exercise in the ARG trial than CON trial (P < 0.05). Femoral artery blood flow increased 270% above basal in the exercised leg (P < 0.001) but not in the nonexercised leg, with no differences between the ARG and CON trials. Mixed and myofibrillar MPS were both greater in the exercised leg compared with the nonexercised leg (P < 0.001), but did not differ between the ARG and CON treatments. We conclude that an oral bolus (10 g) of arginine does not increase NO synthesis or muscle blood flow. Furthermore, arginine does not enhance mixed or myofibrillar MPS either at rest or after resistance exercise beyond that achieved by feeding alone.

[GeneGnomeX]

The group in the abstract below has done the majority of the nitrate/performance studies, and I don't know why they were able to measure an increase in plasma nitrite with a 6g dose and others have not, but wanted to make everyone aware of this. This study design is identical in design to the 3 others they have done with beetroot/nitrate.

If they are able to replicate the result and other labs can as well we may not have seen the end of arginine for performance. I don't think it is of much benefit for weight training/muscle building though.

I can imagine arginine is way cheaper, anyway than nitrate.

J Appl Physiol. 2010 Nov;109(5):1394-403. Epub 2010 Aug 19.
Acute L-arginine supplementation reduces the O2 cost of moderate-intensity exercise and enhances high-intensity exercise tolerance.
Bailey SJ, Winyard PG, Vanhatalo A, Blackwell JR, DiMenna FJ, Wilkerson DP, Jones AM.

School of Sport and Health Sciences, St. Luke's Campus, University of Exeter, Exeter, United Kingdom.
Abstract
It has recently been reported that dietary nitrate (NO(3)(-)) supplementation, which increases plasma nitrite (NO(2)(-)) concentration, a biomarker of nitric oxide (NO) availability, improves exercise efficiency and exercise tolerance in healthy humans. We hypothesized that dietary supplementation with L-arginine, the substrate for NO synthase (NOS), would elicit similar responses. In a double-blind, crossover study, nine healthy men (aged 19-38 yr) consumed 500 ml of a beverage containing 6 g of l-arginine (Arg) or a placebo beverage (PL) and completed a series of "step" moderate- and severe-intensity exercise bouts 1 h after ingestion of the beverage. Plasma NO(2)(-) concentration was significantly greater in the Arg than the PL group (331 ± 198 vs. 159 ± 102 nM, P < 0.05) and systolic blood pressure was significantly reduced (123 ± 3 vs. 131 ± 5 mmHg, P < 0.01). The steady-state O(2) uptake (VO(2)) during moderate-intensity exercise was reduced by 7% in the Arg group (1.48 ± 0.12 vs. 1.59 ± 0.14 l/min, P < 0.05). During severe-intensity exercise, the Vo(2) slow component amplitude was reduced (0.58 ± 0.23 and 0.76 ± 0.29 l/min in Arg and PL, respectively, P < 0.05) and the time to exhaustion was extended (707 ± 232 and 562 ± 145 s in Arg and PL, respectively, P < 0.05) following consumption of Arg. In conclusion, similar to the effects of increased dietary NO(3)(-) intake, elevating NO bioavailability through dietary L-Arg supplementation reduced the O(2) cost of moderate-intensity exercise and blunted the VO(2) slow component and extended the time to exhaustion during severe-intensity exercise.

PMID: 20724562 [PubMed - in process]

[G.W. Hayduke]

<--- has been using beets for 4 years now.

You guys are way behind.