Exercise bestows many benefits from increased quality of life,¹ to better sleep,² increased cognitive function,³ better hormone regulation,⁴ increased bone density⁵ and, of course, better weight management.⁶ As the benefits of exercise and the disadvantages of sedentary work lives are harder to ignore, more people consider themselves to be "athletes." If not that, they at least see themselves as having active lifestyles. These now include everyone from those who participate on a professional or Olympic level to the millions of Baby Boomers, Gen Xers and Millennials who participate in sports or hit the gym to maintain health. Whether it's for personal achievement or serious competition, ask anyone and he'll say he feels better when he's consistently exercisingthat is if he doesn't face injury, can sustain his energy to do the activities he prefers and isn't too sore afterwards.

Those are the three big reasons athletes, one-time gym hitters and those in between seek supplements for sports nutrition: injury prevention, energy and recovery. And, natural ingredients have been able to rise to the challenge in myriad ways. Even as FDA increases enforcement to ensure products do not contain illegal substances, the sports nutrition market is offering innovative products from chews to capsules, drinks, gels, stick packs, bars and strips. Drinks or beverage shots offer a nice vehicle for water-soluble compounds, while capsules and bulk powdered mixes may be the best solution for formulas that contain high doses of ingredients.

Athletes want results, ease of delivery and affordable price points. And they want clean products (i.e, no artificial, unpronounceable ingredients) backed by scientific research. Certainly keeping products natural can build brand loyalty, but showing documentation of efficacy can create not just loyal consumers, but product fans.

Next: Botanicals

Botanicals

Herbs and plant-based ingredients offer an abundance of antioxidants, which assist in reducing the free radical load that comes from elevated cellular respiration during exercise. Free radicals can lead to aging and degenerative health conditions, and can negatively affect muscle tissue. Antioxidants can also enhance endothelial nitric oxide (NO) synthase expression and subsequent NO release from endothelial cells. NO can increase blood flow to muscles and other organs, which can boost performance.

Beets naturally contain nitrate and may give athletes that extra edge in sports. Nitrate can widen blood vessels, reducing blood pressure and allowing more blood flow, and it can affect muscle tissue, reducing the amount of oxygen needed by muscles during activitytwo things that benefit athletes. Researchers from the University of Exeter, England, reported drinking beet juice enabled competitive-level cyclists to reduce the time it takes to ride a given distance.⁷ On average, riders were 11 seconds (2.8 percent) quicker over a 4-km distance and 45 seconds (2.7 percent) faster over a 16.1-km distance. In a follow-up study, many of the same researchers reported beet juice helped athletes who were exercising in a low-oxygen state by helping maintain muscle metabolic function, and restoring exercise tolerance and oxidative function.⁸

Pterostilbene, naturally found in small berries (blueberries, huckleberries, grapes, etc.), can act as a vasodilator by activating endothelial NO synthase. A 2005 study found pterostilbene induced NO synthase, especially in the presence of quercetin.⁹ As an antioxidant, pterostilbene also reduces free radical damage.¹⁰

French maritime pine (Pinus pinaster Ait.) has been shown to help athletes in a number of ways. Pycnogenol® (from Horphag Research), an extract from the tree's bark, augmented endothelium-dependent vasodilation by increasing NO production in a double blind, randomized, placebo-controlled study  conducted on healthy students in Japan who consumed Pycnogenol for two weeks.¹¹  The supplement significantly enhanced the ability of arteries to expand to facilitate better flow of blood. A review of Pycnogenol studies in 2002 reported more than 17 clinical trials described a strengthening of capillary walls after supplementation.¹² That review also noted Pycnogenol strengthens veins as well as micro-vessels to prevent swellings (edema), micro-bleedings and hemorrhages. A further placebo-controlled clinical study with 66 healthy recreational sports athletes found those who took Pycnogenol experienced less muscle cramping and pain after exercise than when they weren't taking the supplement.¹³

The botanical bitter orange (Citrus aurantium) is known for stimulating thermogenesis, increasing the percentage of lean muscle and improving athletic performance. In a three-arm, double blind, placebo-controlled, crossover study, 10 healthy adults (three women) aged 20 to 31 ingested one dose of Ripped Fuel Extreme Cut®, a dietary supplement that contains 21 mg synephrine (as AdvantraZ from Nutratech) and 304 mg caffeine under resting conditions and one hour prior to moderately intense exercise (30 minutes of cycling) with a placebo/exercise control.¹⁴ Exercise was perceived as less strenuous for those who took the supplement, and no significant adverse events occurred. And a 2011 study found ingesting a product containing bitter orange extract (as AdvantraZ), caffeine and green tea extract increased fat oxidation in certain populations, but did not lead to increased cardiovascular stress.¹⁵

Furostanol glycosides isolated from fenugreek (Trigonella foenum) have been shown to increase muscle mass, even in situations where subjects had decreased testosterone production. A study in castrated rats showed Testofen® (from Gencor Nutrients), at a dose of 35 mg/kg/d, significantly increased the weight of the levator ani (pelvic) muscle without increasing the blood urea nitrogen (BUN) similar to exogenous testosterone (10 mg/kg) treatment, indicating anabolic activity.¹⁶  A 2009 randomized, double blind, placebo-controlled study on Testofen found the proprietary extract produced a positive effect on quality of life in self‐reported satisfaction with muscle strength, energy and well‐being.¹⁷ Additionally, an eight-week prospective, double blind, randomized, placebo controlled, unpublished study showed those in the Testofen group experienced a significant reduction in serum creatinine levels (signifying creatine uptake and recycle in muscle cell) and better maintained muscle size compared to placebo. The study also showed those who took Testofen experienced a significant decrease in body fat compared to baseline.

Capsicum, also known as red hot pepper, can aid athletes in pain management and metabolic boosting. A 1994 quantitative overview of trials of topical capsaicin reported capsaicin cream was better than placebo in providing pain relief.¹⁸ The proprietary hot red pepper extract Capsimax from OmniActive Health Technologies promoted a lipolytic effect as measured by an increase in free fatty acids and glycerol in blood compared to placebo in a 2010 study.¹⁹ Researchers found plasma free-fatty acids increased after ingestion two hours before exercise and one minute post-exercise compared to placebo, and plasma glycerol concentrations increased significantly four hours after ingestion. Numerous other studies have shown the ingestion of red pepper decreases appetite and subsequent protein and fat intakes.^{20, 21}

Next Page: Vitamins and Minerals

Vitamins and Minerals

Niacin (vitamin B3) is converted to nicotinamide in the body for use in the nicotinamide adenine dinucleotide (NAD) pathway. Nicotinamide riboside (NR) can help adenosine triphosphate (ATP) production. Muscles use the chemical ATP as an energy supply, but one of the key requirements for ATP production is a steady supply of NAD. NAD production has its own rate-limiting steps, typically in the conversion of niacin to NAD; niacin flush can also limit consumer interest in supplementing with vitamin B3 even though it can produce increased energy. One way around this is to supplement with NR, which uses a back door, so to speak, to NAD production because it can insert itself in to the NAD recycling pathway. Along with increasing the longevity sirtuin genes, NR is theorized to increase ATP production.²²

The mineral potassium can play a major role in hydration, especially for those who are sweating on the field or in the gym. Local muscle fatigue may be related to potassium efflux from the muscle cell and/or lactate accumulation within the muscle.²³ A 2010 study reported the consistent relationship of ventilation and blood potassium levels during exercise suggests a role for this ion in the control of ventilation during physical activity.²⁴ A 2010 Brazilian study reported potassium chloride supplementation reduced the nociceptive (a type of pain) threshold in spontaneous hypertensive rats that exercised; the lack or delay of pain perception may impede detection of angina and myocardial infarction.²⁵

While many are warned too much salt in the diet can harm heart health, athletes can often be depleted of this essential electrolyte. A study conducted at the HEAT Institute, West Chester University, PA, examined sweat sodium losses in a large cohort of American football players.²⁶ While the researchers noted sweat sodium concentration and daily sodium losses ranged considerably, they said heavy, salty sweaters require increased dietary consumption of sodium during preseason. And a 2009 study reported sodium intake during prolonged exercise in the heat played a significant role in preventing sodium losses that may lead to hyponatremia, a metabolic condition where not enough sodium is in the body fluids.²⁷

Next: Protein and Amino Acids

Protein and Amino Acids

Protein is made up of amino acids, and athletes who supplement with protein can increase energy, muscle building and recovery.  Protein can come in plant and animal forms, but research has shown dairy protein (whey and casein) are better for building muscles than soy.²⁸ Other studies report soy does stimulate muscle synthesis, just not to the extent of other protein.²⁹

Similarly to protein, peptides are molecules formed by joining two or more amino acids. When the number of amino acids is fewer than about 50, these molecules are named peptides, while larger sequences are referred to as proteins. Exercisers can benefit from peptide supplementation; for instance, PepForm (from Glanbia) is a platform of peptides designed for improved bioavailability and functionality of amino acids, as well as other functional ingredients such as herbals. PepForm Leucine Peptides is a patent-pending high-leucine (more than 40 percent) peptide product that uses PepForm technology to bind L-leucine and other amino acids. An unpublished study from Glanbia Nutritionals reported PepForm Leucine Peptides delivered the amino acid L-leucine in a soluble and bioavailability form, which allowed muscle growth at a higher rate than free-form amino acids.

Some choose to supplement with specific amino  acids to achieve athletic results. A 2011 review from ConsumerLab.com noted supplements with the amino acid L-arginine increased intense exercise endurance in older and recreational athletes. L-arginine can, in some people, increase NO, according to the review. In a 2009 study, dietary L-arginine supplementation promoted muscle over fat gain, improved the metabolic profile and reduced body white fat in diet-induced obese rats.³⁰ And a 2006 French study found heart failure patients who supplemented with L-arginine enhanced exercise endurance, improving physical fitness.³¹

Branched-chain amino acids (BCAAs), when administered before exercise, affect the response of some anabolic hormones, mainly human growth hormone and testosterone, which helps boost performance.³² BCAA supplementation before and after exercise also has beneficial effects for decreasing exercise-induced muscle damage and promoting muscle-protein synthesis.³³

L-carnitine, biosynthesized from the amino acids lysine and methionine, is required for the break down of fats into energy. An increasing body of scientific evidence illustrates the favorable effects of L-carnitine for athletes and physically active people in regard to performance, fatigue and recovery.³⁴ In a 2004 review, Austrian researchers said evidence supports a beneficial effect of L-carnitine supplementation in training, competition and recovery from strenuous exercise and in regenerative athletics.³⁵ And a 2008 review from the University of Connecticut noted L-carnitine demonstrated promising findings for cardiovascular diseases, which shows it might allow for enhanced physical activity.³⁶

Carnipure, a branded L-carnitine tartrate ingredient from Lonza, has been studied for its role in the exercise recovery process. Most studies were conducted at the University of Connecticut, Storrs. In the early 2000s, this team found evidence that elemental L-carnitine provided by Carnipure reduced the effect of hypoxia (when the body is deprived of adequate oxygen) after resistance exercise, resulting in less tissue damage, reduced muscle soreness and quicker recovery.³⁷ Later, they reported this effect is probably due to Carnipure's ability to increase oxygen uptake.³⁸ The University of Connecticut team found another use for Carnipure in exercise recovery in 2006: 2 g/d of elemental L-carnitine provided by Carnipure increased androgen receptor content at rest and enhanced testosterone levels after resistance exercise.³⁹ A year later, they found 1 g of elemental L-carnitine was as effective as 2 g in mediating various markers of metabolic stress and muscle soreness.⁴⁰ Carnipure supplementation in healthy individuals also improved postprandial blood flow in a study that used a high-fat meal as a model to slow blood flow.

An unpublished study provides evidence to support use of Carnipure in exercise recovery in Baby Boomers, according to Lonza. The data showed 2 g of elemental L-carnitine reduced chemical damage to tissues after exercise and optimized muscle repair and remodeling.

Creatine, a molecule derived from the amino acids glycine, arginine and methionine, is effective for activities that involve repeated short bouts of high-intensity physical activity.⁴¹ According to a review from the University of Oklahoma, creatine significantly increased force production regardless of sport, sex or age.⁴² The review also reported activities involving jumping, sprinting or cycling generally showed improved sport performance following creatine ingestion.

Kre-Celazine® (from All American Pharmaceutical), a combination of esterified fatty acid carbons and creatine, can reduce inflammation and pain, thus improving sports performance. A 2009 study reported Kre-Celazine exerted its greatest impact on areas of inflammation/pain in the extremities, as well as in the neck and shoulder region.⁴³ An additional unpublished study from 2007 performed by BioCeutical Research and Development Laboratory, Billings, MT, reported 12 out of 12 subjects who had arthritis, joint pain and inflammation said they experienced some to significant benefits from taking Kre-Celazine  for four weeks over conventional prescription and OTC arthritic and pain drugs. All American Pharmaceutical also offers Kre-Alkalyn®, a buffered creatine, which was found to decrease joint pain in professional football players due to inflammation and direct bruising, while increasing endurance and stamina in an unpublished study.

Next: Specialty Nutrients

Specialty Nutrients

PhosphatidylSerine (PS), a phospholipid component, can prevent the negative effects of the stress hormone cortisol, which can inhibit sports performance. A 2008 study reported a moderate dose of PS (600 mg/d) reduced plasma concentrations of cortisol and increased the testosterone to cortisol ratio in healthy males who were following a weight-training program.⁴⁴ Another randomized, double blind, placebo-controlled study concluded six weeks of PS supplementation reduced perceived stress levels in golfers and significantly improved the number of good ball flights during tee-off for healthy young golfers with handicaps of 15 to 40.⁴⁵

PS is also known for its cognitive health-boosting properties, and making quick decisions and reducing the amount of errors during a competition can be crucial to success. A randomized, double blind, placebo-controlled, crossover pilot study found 400 mg/d PS (as SerinAid®, from Chemi Nutra) reduced the time needed for a correct calculation by 19.8 percent and reduced the total amount of errors by 33 percent in males, aged 18 to 30, who consumed the supplement before acute bout of resistance training.⁴⁶

Alpha-Glyceryl Phosphoryl Choline (A-GPC), an acetylcholine precursor, can increase neuromuscular communication within the body and brain, which leads to heightened mental focus and sports performance. A-GPC promotes the secretion of growth hormone, which regulates metabolism and body composition. A 2010 study reported acute and prolonged (four weeks) ingestion of a supplement containing A-GPC; choline bitartrate; PS; vitamins B3, B6 and B12; folic acid; L-tyrosine; caffeine; acetyl-L-carnitine; and naringin helped subjects maintained better reaction time and subjective feelings of focus and alertness to both visual and auditory stimuli compared to placebo.⁴⁷ Another study showed a single 600-mg dose of A-GPC (as AlphaSize, from Chemi Nutra), when administered 90 minutes prior to resistance exercise, increased post-exercise serum growth hormone and peak bench press force.⁴⁸

Phosphatidic Acids (PA) are a part of phospholipids that are essential for lipid synthesis and cell survival. According to Chemi Nutra, a study on branded Mediator® PA (expected to be published in 2012) exhibited noticeable effects on muscle mass and strength in male subjects engaged in weight lifting exercise.

Ribose, a kind of sugar produced by the body, has been used as a supplement to accentuate the bodys natural process of energy synthesis. Ribose is a five-carbon sugar; however, unlike other sugars, it is not burned for fuel; instead, its absorbed into cells for ATP production. Ribose may help muscles regenerate lost energy and potentially minimizes physiological consequences of exercise. Ribose also plays a role in the synthesis of coenzyme-A, flavin adenine dinucleotide (FAD), NAD, riboflavin (vitamin B2), DNA and RNA, all which promote a healthy metabolism. A 2004 Danish study found 200 mg/kg body weight of ribose restored muscle ATP faster than placebo 72 hours after cycle training.⁴⁹ The researchers said results supported the hypothesis that the availability of ribose in the muscle is a limiting factor for the rate of resynthesis of ATP. In a 1991 study, ribose served as an energy source and enhanced the de novo synthesis of purine nucleotides.⁵⁰ Nucleotides are molecules that, when joined together, make up the structural units of RNA and DNA, and purine nucleotides form hydrogen molecules in DNA. In this study, post-exertional muscle stiffness and cramps disappeared almost completely in two of the three subjects. Still, other studies have found oral ribose supplementation (10 g/d for five days) did not affect anaerobic exercise capacity or metabolic markers in trained subjects,51 and oral ribose supplementation (4-g doses four times a day) did not beneficially impact post-exercise muscle ATP recovery and maximal intermittent exercise performance.⁵²

Methylsulfonylmethane (MSM), an organosulfur compound, can benefit athletes by cushioning joints, especially when it's used in combination with glucosamine. MSM (3 g twice/d) improved symptoms of pain and physical function in patients with knee pain without major adverse events in a study from Southwest College Research Institute, Tempe, AZ.⁵³ Compared to placebo, MSM produced significant decreases in pain and physical function impairment. And a 2004 study from India found adding MSM and glucosamine produced an analgesic and anti-inflammatory effect in osteoarthritis (OA) patients.⁵⁴ OptiMSM® (from Bergstrom Nutrition), at 3g tid, produced significant decreases in pain and physical function impairment scores in OA patients.⁵⁵ Another study showed it decreased inflammation markers in an animal model.⁵⁶

Natural eggshell membrane is another specialty ingredient marketed for joint health that can help keep athletes flexible. NEM® (from ESM Technologies) naturally contains glucosamine, chondroitin, hyaluronic acid (HA) and collagen, all of which support joint health. A 2009 study found a 500-mg/d dose of NEM reduced pain and stiffness and increased flexibility in seven to 10 days.57 Researchers believe its efficacy is the result of its anti-inflammatory properties. A 2011 in vitro study reported NEM has the ability to reduce the inflammatory marker tumor necrosis factor alpha (TNF-alpha).58

Consumers want to be the best they can beon the field, in the gym and in a swimsuitand exercise can get them there while adding mental and stress-relieving benefits. Natural ingredients formulated in supplements, gels, beverages, etc., can help everyonefrom the mom on the Stairmaster to the Ironman triathlete competing at the World Championship in Hawaiiprevent injury, recover and sustain energy while they are sweating to whichever activity they love.

More on Joint Health:

References listed on the next page.

References:

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