A new study has found that a popular nutritional supplement that is claimed to lead to greater muscle strength by increasing blood flow to working muscles, does not in fact have any appreciable effect.
In recent years, various nutritional supplements have been developed containing arginine-alpha-ketoglutarate (AAKG) and it has been claimed that the supplement-enhanced blood flow to working muscles during resistance exercise provides greater muscle strength than that achieved purely by exercise.
The report by researchers at Baylor University in Texas and published in the International Journal of Sport Nutrition and Exercise Metabolism, studied the effects in 24 men of seven days of AAKG supplementation using the nutritional supplement NO2 PlatinumTM on arterial blood flow in the arms after a single bout of resistance exercise.
The results showed that seven days of AAKG supplementation had no significant impact on blood movement or increased brachial artery blood flow in response to a single bout of resistance exercise.
“We did see a slight increase in blood flow but those effects can only be attributed to the resistance exercise and not to the supplement,” said study author Dr. Darryn Willoughby.
“The data appears to refute the alleged supposition and manufacturers’ claims that ‘vasodilating supplements’ are effective at causing vasodilation, thereby resulting in increased blood flow to active skeletal muscle during resistance exercise.
Furthermore, we specifically demonstrated that a single bout of resistance exercise increases vasodilation, arterial blood flow and circulating nitric oxide levels, but that the AAKG supplement provided no additive, preferential response compared to a placebo.”