Erin Lewis

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Nitric oxide (NO) is a naturally occurring substance in the body. It is released during exercise, stimulating vasodilatation, which increases blood flow to the muscles. It has become a popular form of supplementation in the past few years, gaining popularity over creatine use (which it is now often stacked with). Companies introduced nitric oxide as a supplement similar to creatine; naturally occurring in the body to aid in exercise, and by increasing the supply, they claim that it would enhance the user’s exercise capacity. However, there are few studies done that test the actual physiological effects of nitric oxide supplementation on exercise, and even fewer that use a placebo incorporating caffeine to isolate the effects of nitric oxide itself. An increase in vasodilatation at the muscle tissue, increasing blood flow, also increases the amount of oxygen readily available to the tissue. Therefore, claims have been made that nitric oxide supplements increase mental acuity and focus, muscle fullness via “blood-engorged pumps”, increased fat loss, increased strength, power, and endurance, and creatine retention. Since the product claims to improve exercise performance via increased vasodilatation and blood engorgement, it would be appropriate to investigate respiratory responses during exercise. An increase in oxygen delivery could theoretically increase oxygen consumption; or the oxygen extracted from red blood cells at the tissue level. The best way to test the claim for mental acuity, endurance, and recuperation is to take the user’s rate of perceived exertion and record the amount of time they can exercise. To truly test maximal oxygen consumption and exertion, a graded maximal exercise must be used. Nitric oxide supplements also have large amount of caffeine in the product due to caffeine's effects as an ergogenic aid. Therefore to test the effects of nitric oxide supplementation alone, a placebo stacked with caffeine must be used.


Kinesiology | Life Sciences

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