Nitric Oxide Ingredients for Sports

Serious athletes train hard and pay keen attention to how they nourish their bodies. Sports supplements formulated to keep athletes in peak condition generally fall into one of two categories: endurance enhancers or recovery aids. In recent years, the sports nutrition category has flourished with many new ingredients that are backed by scientific studies-much to the delight of the category’s core consumers who have become increasingly wary of products that deliver little more than empty promises.

Of the aforementioned sports dietary supplement ingredient categories, endurance is currently the most rapidly evolving. Sports supplements that enhance endurance typically center on the premise of increasing the body’s natural production of nitric oxide (NO), which increases blood flow (vasodilation), thereby improving the body’s ability to make heightened use of oxygen and nutrients in the muscles. The result is, ideally, an increase in performance potential.

As a precursor to nitric oxide, L-arginine has long been a go-to endurance enhancing ingredient, but there is substantial buzz around a new crop of products capable of producing a similar, if not improved, effect.

Launched in May, Nitrosigine from Nutrition 21 LLC (Purchase, NY) is a patented source of inositol-stabilized arginine silicate with FDA new dietary ingredient (NDI) status. In a preclinical study led by James Russell of the University of Alberta, researchers investigated its metabolic effects and found that it raised blood arginine levels and was  “more biologically effective” than arginine hydrochloride.

Pointing to Nitrosigine’s enhancement of coronary blood flow, Russell deems the ingredient a good fit for sports nutrition.

Researchers from Kyowa Hakko USA (New York City), led by Darryn Willoughby of Baylor University, recently discovered that the potential of the amino acid L-citrulline rivals that of L-arginine. The company presented its latest findings earlier this year.

“Our study found 1.6-fold increases in arginine blood levels with L-citrulline administration as compared to L-arginine administration,” said Danielle Citrolo, PharmD, manager of technical services for Kyowa Hakko USA. “This tells us we are able to achieve more effective levels of blood arginine with citrulline than by taking arginine itself. Our data presented was in animals, but this was also demonstrated in humans by Schwedhelm E. et al.”

Kyowa Hakko conducted two human studies-one that focused on blood flow enhancement and one on recovery benefits.

In the first study, researchers confirmed an increase in peripheral blood flow by monitoring the temperature of a hand immersed in cold water. “Supplementation with citrulline enhanced the blood flow in the hand, and it was statistically significant as compared to baseline,” said Citrolo. “Oral citrulline (800mg) showed an effect in raising body surface temperature in the neck, shoulders, and right palm. We believe this is most likely due to increased blood flow due to citrulline-induced vasodilation.”

The second study focused on blood pressure, using the ankle as the point of measurement (the brachial-ankle pulse). Researchers found that after seven days of L-citrulline supplementation there was a statistically significant improvement in the blood pressure, leading to the conclusion that short-term L-citrulline supplementation possibly delivers functional improvement for arterial stiffness.

Vinitrox from Nexira (Rouen, France), anothervasodilation ingredient, is comprised of apple and grape polyphenols. According to Mathieu Dondain, director of marketing and communication, preliminary ex vivo and in vitro studies have confirmed ViNitrox’s specific vasodilating properties.

“The first study conducted by Nexira showed ViNitrox’s dilating effect on the endothelium in isolated rat aortas,” he says, adding that the ex vivo study confirmed increased vasodilation by 50%. “These vasodilating properties have been confirmed and demonstrated by two other studies which show that ViNitrox significantly boosts NO production and induces endothelial NO synthase (eNOS) activation.”

Sidebar: Recovery Roundup

Ingredients that help muscles recover post-training are an important part of increasing athletic performance:

• ProHydrolase: A multi-enzyme formulation from Deerland Enzymes (Kennesaw, GA) supported by several in vitro tests, ProHydrolase is billed to be “bio-sufficient,” including all the tools required to break proteins down into a bio-usable form, regardless of endogenous enzyme output.
• Nexrutine: A proprietary blend of Phellodendron amurense bark extract from Next Pharmaceuticals (Salinas, CA), Nexrutine inhibits the gene expression of the COX-2 enzyme, which is responsible for swelling and pain.
• BioCore Recovery Acute: This formula from National Enzyme Co. (Forsyth, MO) consists of proteolytic enzymes such as bromelain, and antioxidants and minerals to support post-exercise tissue recovery and delayed onset of muscle soreness.
• L-carnitine: Exercise can deplete cellular oxygen (hypoxia). Carnipure L-carnitine, manufactured by Lonza (Basel, Switzerland), is scientifically proven to restore endothelial cells during times of metabolic stress/exercise, increasing endothelial cell integrity and blood flow to tissues.
• OptiMSM: A GRAS-designated proprietary and patented form of MSM (methylsulfonylmethane) from Bergstrom Nutrition (Vancouver, WA) minimizes muscle damage and soreness caused by exercise. It is also said to increase antioxidant capacity and support healthy joints and range of motion.

Sidebar: Performance Boosters

Ingredients that deliver performance increase can give athletes a competitive advantage:

• Ribose: Every cell in the body contains ribose, a compound that enables cells to circumvent the slow process of energetic recovery. “Supplemental D-ribose salvages biochemical constituents and improves overall cellular performance,” says Michael Crabtree, sales manager for sports nutrition and supplements at Bioenergy Life Science Inc. (Minneapolis), a supplier of ribose.
• Creatine: Creatine MagnaPower from Albion Human Nutrition Division (Clearfield, UT) combines magnesium and creatine in a synergistic, patented chelate for optimal ATP synthesis. This, in turn, enhances the energy required for intense anaerobic activity. Kre-Alkalyn from All American Pharmaceutical (Billings, MT) is another creatine ingredient, and it possesses a patented stability.
• Wellmune WGP: This beta 1,3/1,6 glucan derived from a proprietary strain of baker’s yeast from Biothera (Eagan, MN) is backed by nine clinical studies confirming its ability to boost health-imparting neutrophils (immune cells) that can be temporarily weakened after high-intensity exercise.
• HMB: B-hydroxy b-methylbutyrate (HMB) is naturally produced by the body during the metabolism of the branched chain amino acid leucine. HMB is said to increasing muscle protein by enhancing protein synthesis and decreasing protein breakdown.
• Betaine: BetaPower natural betaine from DuPont Nutrition & Health (Madison, WI) is a purified form of anhydrous betaine derived from the molasses of sugar beets. It is billed to improve physical performance, especially strength, power, and muscle endurance.
• ModCarb: A maltodextrin alternative, ModCarb from FutureCeuticals (Momence, IL) is a patented functional energy food derived from organic whole grains, including quinoa, amaranth, oats, buckwheat, millet, and chia. It delivers a sustainable source of glucose.  
• elevATP: elevATP is a proprietary blend of plant-derived trace minerals (ancient peat) with a polyphenol-rich apple extract (Malus) from FutureCeuticals. The ingredient is clinically proven to stimulate the body’s production of ATP at the mitochondrial level, by an average of 64%, without increasing lactic acid.
• Whey Protein: Whey is the gold standard of sports proteins due to its rounded essential amino acid profile and branched-chain amino acid content. Lacprodan Hydro.365 brand whey protein hydrolysate from Arla Foods Ingredients (Århus, Denmark) reportedly boasts quick absorption properties to optimize post-training recovery, blood plasma insulin response, and amino acid absorption.