So we have all heard about supplements before. Supplements by definition are something that completes or enhances something else when added to it. A dietary supplement is something that enhances one’s diet to meet or exceed the needs. Well at least that’s how I’m going to define it. Naturally, supplementation is a big aspect within fitness, whether you agree with it or not.
Personally, I have used plenty of supplements before, ranging from fish oil, L-lysine and vitamin C to pre-work outs, post-work out protein to test boosters and pro-hormones. And yes I will continue to take supplements. Really, supplements are what sparked my interest in exercise physiology in the first place. I wanted to know more than the nit wit at GNC giving me his pathetic sales pitch (sorry for those that work in stores like GNC, had to say it). With this article I want to take a look at what I believe is one of the most talked about and the most confusing ingredient/ideals in performance supplements today.
Go to GNC or any other store and try to find a store that doesn’t have a product that contains Nitric Oxide or talks about increasing NO levels, I dare you…..double dog dare you. Heck, we sell products like that in our gym. That’s how much emphasis is put on one idea, increasing serum NO levels. Well let’s take a look at what exactly NO is the physiology behind NO and does it have any ergonomic effect during exercise. I’m about to drop some knowledge on dat ass.
*I want to stress that nothing will ever be as effective as the correct diet and the right training type to achieve your’ goals. We are only looking at one ingredient, Nitric Oxide not a whole pre-work out product.*
First off, NO was found when scientists in 1998, Robert F. Furchgott, Louis J. Ignarro and Ferid Murad were trying to identify the vasodilator known as “EDRF” or endothelium-derived relaxing factor (Moncada, 2006). However, it was until 2001 that Ed Byrd, founder of former supplement company MRI, brought NO to the bodybuilding world under the company. Ed has an extremely long history with bodybuilding – he co- founded EAS and was involved in bringing Creatine to market. In fact, he refers to himself as “Mr. Creatine”.
In short, it’s a cell signaling molecule that is involved in numerous functions, mainly initiating vasodilation. One of the reasons why increasing blood vessel size is important in exercise performance is that nutrients are delivered faster and waste products are removed faster, allowing for faster recovery between sets and between workouts and ultimately better workout performance because you’re getting fuel to your muscles faster (Bloomer et al, 2011). The marketing of products that contained NO are generally based on the assumption that increased blood flow to exercising muscle will enable increased: levels of work output, resistance to fatigue with submaximal levels of work, and recovery following exercise. With these claims, supplementations containing NO quickly increased drastically over the past few years without much research behind the product. It wasn’t until recently that studies looked at the effects of NO supplementation with exercise.
Nitric Oxide is synthesized in the endothelium from its precursors, L-arginine and L-citrulline via enzymatic action of nitric oxide synthase (eNOS). In the blood vessels, NO is produced by the platelets where it is released and acts to inhibit adhesion and aggregation between platelets (Moncada, 2006). In the blood vessel collectively, NO acts as a sodium distributer and vessel vasodilator. Furthermore, NO generation directly affects blood pressure in humans. In relation to blood pressure control by NO, there are two types of levels: hypertension and hypotension. Hypertension is the increase of blood pressure due to vasoconstriction and hypotension is the decrease of blood pressure due to the dilation of the blood vessels.
Nitric Oxide also provides other vascular effects including anti-thrombotic, anti-inflam and anti-proliferative effects. Overall, NO is an important substrate that regulates certain things in the body.
So does it work in relation to exercise? Well, let us look at the science. In theory, the effects of NO supplementation during moderate to intense exercise show promise. However, not everything works in conjunction with theory. The reality of NO supplementation during training is that the body does not concentrate all of oral nitric oxide towards blood vessel vacuolization.
Researchers have attempted to find oral-supplemented NO involvement in skeletal muscle response to resistance and endurance training. In an early study, researchers showed that NO levels were unaffected during steady hand-gripping exercise after administration of NO synthase blocker, L-NMMA, orally (Dyke et al, 1995). This test showed that nitric oxide levels were not present during minimal exercise. Think about it, if NO levels were too decreased with the administration of the blockers then nitric oxide would be aiding the increase of blood flow to the forearms during the isometric exercise. However, the administration of L-NMMA via the phrenic artery during certain contractions in animal based test showed vasoconstriction; suggesting the presents of NO during extended exercise bouts (Dyke et al, 1995).
A population was then infused with Ach, a NO stimulant, and underwent the same exercise; furthermore, a control population went through the same exercise. The control population had a forearm blood flow average of 7.1 ml with a deviation of 1.2 ml after 9 minutes of exercise (Dyke et al, 1995). The population receiving infused Ach had a forearm blood flow average of 13.3 ml with a deviation of 1.4ml while the group injected with the NO synthase blocker, L-NMMA, had a blood flow average of 6.2 ml with a deviation of .8 ml (Dyke et al, 1995). The inhibition of NO during hand-gripping exercise showed a reduction of blood flow up to 30% (Dyke et al, 1995). In theory of this study, administration of a NO stimulant increases vacuolization and blood flow to working muscle while administration of an NO inhibitor can cause vasoconstriction of blood vessels, decreasing blood flow. While this study showed a DIRECT EFFECT OF A NO STIMULANT AND BLOOD FLOW TO AN AREA OF EXERCISE, this study ONLY SHOWED THE EFFECTS OF INFUSED ELEMENTS, NOT AN ORAL SUPPLEMENT. So we know that an exogenous supplementation of NO injected directly to the working muscle causes a significant effect on increased blood flow. But who’s going to work out with a needle in their arm injecting themselves with NO after every set? Kevin Van Voris put your hand down.
So is it possible that oral, not infused, nitric oxide supplementation can create an increase of blood flow to working muscles? To date, the evidence showing an increase of NO through oral supplementation is minimal (Bloomer et al, 2011). In a study done, resistance trained males ingested an oral dose of NO after 10 hours of fasting. Heart rate, blood pressure and blood samples were collected 5, 15, 30 and 60 minutes after digestion of either the supplement or a placebo. Results showed that there was no interaction effects were noted for plasma nitrate/nitrite with the values remaining the same across the different time periods for both NO supplementation and placebo (Bloomer et al, 2010). Similarly, no changes in heart rate and blood pressure where seen as well (Bloomer et al, 2010). This was also repeated again on 2 separate occasions with the same results. This shows that an oral ingestion of NO in a healthy, resistance trained population has literally….no effect. See what I did there?
So does Nitric Oxide have any beneficial purposes? Yes, very important ones at that. During a traumatized state, NO is produced in large quantities to protect the body (Moncada, 2006). Contribution of NO production due to stress in humans appears to be around 20% and 30% of the current bioavailability (Green et al, 2004). Furthermore, basal levels of NO production during this time increase large artery density (Fahs et al, 2009). Also individuals that are clinically hypertensive benefit from NO supplementation.
In conclusion Nitric Oxide is an important element for controlling blood flow and vessel size. As far as an exercise supplement, there is a disconnect between theory and practice. A decade ago, these companies started to push that nitric oxide is the new way to “pack the muscle on and get the pump.” While claims sound promising and the physiology is there, the evidence behind oral NO supplementation concludes that there is little to no ergonomic effect. That’s why you have started to see less and less of actual “Nitric Oxide” as an ingredient in products. People began to realize that supplementing with exogenous NO really did nothing. Because of this, companies began to shy away from having NO as an ingredient and started to focus on using the NO substrates to “boost” natural NO levels with an increase in bioavailability of the building blocks. These building blocks, L-arginine, L-citrulline, AAKG, GPLC and others are now the staple ingredients in pre-work out drinks. Do this work or not? The topic is still an open book; however, I will discuss these in further detail later. This review just shows that Nitric Oxide aid for an anabolic effect is very minimal.
Next week, squat clinic part 2. I will go over the set up and movement of the squat. Also I will touch on the common issues with the squat and simple exercises to help you correct and improve your squat. I will do my best to try to include videos and images…I’m still trying to get used to this whole blog thing.
Bloomer, RJ, Farney, TM, Trepanowski, JF, McCarthy, CG, & Canale, RE. (2011). Comparison of pre-workout nitric oxide stimulating dietary supplements on skeletal muscle oxygen saturation, blood nitrate/nitrite, lipid peroxidation, and upper body exercise performance in resistance trained men. Journal of the International Society of Sports Nutrition, 7(16).
Bloomer, RJ, Williams, SA, Canale, RE, Farney, TM, & Kabir, MM. (2010). Acute effects of nitric oxide supplement on blood nitrate/nitrite and hemodynamic variables in resistance trained men. Journal of Strength and Conditioning Research, 10(24).
Dyke, CK, Proctor, DN, Dietz, NM, & Joyner, MJ. (1995). Role of nitric oxide in exercise hyperemia during prolonged rhythmic hand gripping in humans. Journal of Physiology, 488(1).
Fahs, CA, Heffernan, KS, & Fernhall, B. (2009). Hemodynamic and vascular response to resistance exercise with L-arginine. Medicine & Science in Sports & Exercise.
Green, DJ, Maiorana, A, O’Driscoll, G, & Taylor, R. (2004). Effect of exercise training on endothelium-derived nitric oxide function in humans. The Journal of Physiology, 561(1), Retrieved from http://onlinelibrary.wiley.com/doi/10.1113/jphysiol.2004.068197/full
Hauk, JM, & Hosey, RG. (2006). Nitric oxide therapy: fact or fiction?. Current Sports Medicine Reports, 5.
Moncada, S. (2006). Nitric oxide in the vasculature: physiology and pathophysiology. Annals of the New York Academy of Sciences, Retrieved from http://onlinelibrary.wiley.com/doi/10.1111/j.1749-6632.1997.tb51989.x/full
Paddon-Jones, D, Borsheim, E, & Wolfe, RR. (2004). Potential ergogenic effects of arginine and creatine supplementation. American Society for Nutritional Sciences.
Tang, JE, Lysecki, PJ, Manolakos, JJ, MacDonald, MJ, & Tarnopolsky, MA. (2011). Bolus arginine supplementation affects neither muscle blood flow nor muscle protein synthesis in young men at rest or after resistance exercise. American Society for Nutrition.
Weiss, EP, Park, JJ, McKenzie, JA, Park, JY, & Kulaputana, O. (2004). Plasma nitrate/nitrite response to an oral glucose load and the effect of endurance training. Metabolism, 53(5),