Nitric Oxide Supplements - what are the results?
Nitric oxide is a biological compound which assists in blood flow and oxygen delivery. It's known medically as a 'vasodilator', because it helps move blood (and hence oxygen) fast - this is beneficial during exertion such as exercise. It is a neurotransmitter which works as a hormone, to carry chemical messages between the cells.
Your body produces it naturally, but many people who train hard are finding it beneficial to boost their levels via nitric oxide supplements - technically this is a misnomer, as you cannot supplement directly with a gaseous compound! However there are supplements available which contain specific blends of amino acids, particularly arginine - these are catabalized enzymatically leaving nitric oxide as a byproduct, which lead to measurably raised levels of nitric oxide in the bloodstream. Most "nitric oxide supplements" contain mainly arginine-alpha-keto-glutarate, and others are derived from the complementary amino acid, citrulline. But because of the range of chemical pathways involved, it can be difficult comparing different brands of nitric oxide boosting products effectively - different manufactures and reviewers claim varying benefits, and the best advice is probably self-experimentation and careful tracking.
The benefits of nitric oxide supplementation have mainly been explored amongst the strength training community, who are generally efficient self-experimenters and trackers, good at isolating and testing specific factors that make a difference. Lots of evidence is building that increasing the body's nitric oxide levels leads to significant muscle gain, as well as overall raised endurance and strength - this makes sense, if it helps more oxygen and blood glucose get delivered to the muscles during training, and also during recovery time afterwards. Endurance trainers quickly exhaust their muscles' glycogen supply of energy, and need to metabolise blood glucose directly - by increasing blood oxygen saturation, increased nitric oxide levels will directly faciliate this.
Nitric oxide supplementation has also been found to have a detoxifying effect, supporting liver and kidney function, and other users have reported improvements in erectile dysfunction and male sex drive generally. However it doesnt stimulate or affect the hormones that regulate sexual function, and as such women shouldnt fear taking it for this reason. The detoxifying action is likely to be beneficial to strength trainers, because it speeds the excretion of lactic acid and carbon dioxide in the muscles after training - this will reduce aching and fatigue, and boost recovery time.
Before supplementing with any nitric oxide boosting product, body builders should note that many protein powders are commonly fortified with arginine - so it's important to watch overall intake, as too much arginine can cause side effects of diarrhea and nausea. There are no specific recommendations for daily amounts, but careful tolerance testing is probably wise before using in large quantities. Many regular users cycle their intake, supplementing for one month then abstaining the next - this is a good way to track changes if nothing else. Remember, only you are responsible for your health and wellbeing, and must listen to your body and your mind in deciding the healthiest way to combine diet, exercise and supplementation.