Nitric Oxide Supplements – Do They Really Work?

Nitric Oxide, also known as NO in training circles, plays an important role in blood flow dynamics by increasing vasodilation, which is to say that blood vessels are dilated allowing more blood to pass

The same benefits are also attributed to nitric oxide’s precursors, the amino acid L-arginine, and nitrate/nitrite. While NO’s influences appear to be only a part of a bigger picture that is comprised of multiple signalling molecules that are responsible for vasodilation in human muscle, the relationship is still complex and not completely understood.

Be that as it may, nitric oxide’s reputation as being the most potent dilator of vascular structures has often lead to unfounded and exaggerated advertisements for it in supplement form. Typically, it’s sold with the promise of accentuated delivery of nutrient- and oxygen-rich blood to working muscles thus increasing the pump effect, exercise performance, muscular development, and post-workout recovery.

Unfortunately, the claims of enhanced muscular strength, endurance, and hypertrophy from vasodilation due to NO supplementation, or its precursors like arginine and inorganic nitrate (sodium nitrate), are mixed, polar, or do not seem to be confirmed by the research. While there are hints of possible improvements in blood flow due to inorganic nitrate ingestion, and encouraging effects on recovery due to the presence of supplemental nitric oxide, the general evidence to support the usage of nitric oxide in healthy populations does not appear to exist in terms of a direct effect on exercise or recovery.

In resistance training, NO enhancement of performance is still unclear, or simply does not show itself to have an effect of any value. The same can be said of its precursor, arginine.

Surprisingly, there is even some question as to if nitric oxide really is essential for the regulation of blood flow response and oxygen delivery during exercise in healthy humans.

Of course, all of this begs the question: why use a specialized supplement that shows such inconsistent and ambiguous study results?

In reality, any opinions on the possible benefits of supplemental nitric oxide in relation to performance and muscular development are merely speculative in nature and are most likely fuelled by supplement industry hype married with wishful thinking.

Where there seems to be some interesting effects in the NO department, however, is in the ingestion of dietary sources of nitrate, particularly from a diet rich in fruits and vegetables, and this from a health standpoint as well as for physical performances. Beetroot juice, in particular appears to be a rich source of dietary nitrate that has been demonstrated to have an enhancing influence on exercise performance parameters. While promising, research on the performance attributes of beetroot juice is still preliminary and requires more data to confirm optimal dosing protocols and benefits, especially in athletic populations engaging in cardiovascular endurance activities.

Information concerning beetroot’s influence on training parameters associated with resistance training protocols designed with the goal of increasing muscle mass are lacking at the moment, so no performance-enhancement conclusions can be drawn for the moment.

All that being taken into consideration, it’s very interesting to note that nitric oxide is increased naturally in a localized and generalized fashion during and after an exercise session. Its production is also an adaptation to regular training, especially when it comes to high-intensity cardiovascular activities. Simply translated, this means that the more an individual is trained, the higher that person’s levels of naturally occurring nitric oxide. This may explain why highly trained individuals do not appear to respond to supplementation with NO or its precursors.

In light of this, it puts into doubt the need for nitric oxide or L-arginine supplements when an individual can increase his or her natural levels of nitric oxide through long-term training and natural food sources.

In the final analysis, the lack of incredible results that are typically attributed to nitric oxide’s potential as an ergogenic aid makes it a sports performance supplement that is merely based on mixed scientific studies, coupled with sensationalistic supplement market hype and anecdotal references.

So, one has to weigh the potential effectiveness of a speculative supplement of this nature against that of another product that has proven itself time and time again in research outcomes.