Nitric oxide enhancers used to be a popular supplement. They were designed to cause vasodilation, increasing oxygen delivery. L-Arginine is the main precursor of NO by nitric oxide synthase (NOS) activity. L-citrulline has been indicated to be a second NO donor in the NOS-dependent pathway, since it can be converted to L-arginine. Arginine is a relatively cheap substance, but some of the NO supplements are very expensive. Here's what you need to know about nitric oxide enhancers:
1. Athletes take this because an increase in NO production may enhance oxygen and nutrient delivery to active muscles and improve tolerance to physical exercise and recovery mechanisms.
2. Specifically, the benefits that your body gains from NO include increased blood flow to muscles and organs as well as better cardiovascular and enhanced lung functions.
3. However, a recent study found that when highly trained subjects were supplemented, no positive effect on performance was indicated.
4. Some side effects can include abnormally low blood pressure, low amount of potassium in the blood, collapsed part of the lung, and worsening of chronic heart failure.
5. If you were wondering, it is also used as a ... um... male enhancer. Please consult with your primary care provider.
The studies speak for themselves. There is no concrete data showing that supplements like these nitric oxide enhancers work. Some will swear by their 'pre-workout' supplement but it is possible that the benefit is mental, like taking a placebo and thinking its a magic pill. These supplements are not worth the price or the potential health risk.
As soon as there are evidence based-recommendations backing a cardiovascular enhancer, I will tell you all about it, I promise!