Sports Nutrition

Modern Day Nutrition for the Weekend Warrior

The ancient Greeks knew that building an athlete required more than rigorous training, consuming appropriate foods and allowing the body time to recover to attain peak performance worthy of Mt. Olympus. Men and women alike still appreciate the art of a chiseled physique, even if adorned on an ancient statue. And today’s “weekend warriors” can challenge the physique, strength and stamina of even Hermes’ speed and Hercules’ strength. Though the attire has changed—or specifically, is now donned—in sports, Ares still summons his call to the athlete warrior—be it to pump iron or pound the pavement—and with the right ingredients, one can build a stronger, leaner body less susceptible to oxidative damage while improving immunity in the process.

Whether designed for women or men, sports supplements are a dominant category within the natural products arena. The global market for sports nutrition products is worth nearly $30 billion (US), with this level projected to rise to $36 billion by 2010, a compound average growth rate of 6.5 percent (Global Industry Analysts Inc.).¹ Of this, the U.S. market is expected to reach $17.5 billion by 2010, a compound growth rate of 6 percent; however, the greatest annual growth rates are expected in Europe at an estimated 9 percent.²

The product market is predominately based around sports beverages, but the growth product segment is in sports/energy bars.³ “In the past, the key targets were athletes, aiming to get a specific performance gain from the use of the products. One of the key changes in the past five years is the increased uptake of the products by the general fitness group,” said Aaron Fanning, associate research scientist, Nutrition and Bioactives Group, Ingredients Innovation.

Pumping Muscle Development and More

Down to the DNA (deoxyribonucleic acid), a fundamental element in sports nutrition is protein. Protein is not just for muscle; it is protein’s amino acids that assist in immune function by increasing antibodies, aiding the hormone and enzymatic systems, building ribonucleic acid (RNA), as well as being a component of the molecular “currency” of intracellular energy transfer— adenosine 5’-triphosphate (a.k.a., ATP). Scientists in the field of protein metabolism admit that protein requirements to optimize results from intense exercise training may be higher than previously suspected.^4,5,6

Soy and whey, two proteins used to increase lean muscle development, are at the forefront of building better biceps. The most complete botanically-derived protein, soy is emerging as a sports supplement in the competitive sports elite.⁷ In comparison to whey, soy improves antioxidant status,^8,9 possibly because of the naturally-occurring isoflavone content.¹⁰ The antioxidant components of isoflavones can diminish oxidative stress caused by exercise, which may lead to fatigue, muscle soreness, inflammation and muscle injury.

Additionally, soy protein contains a high concentration of three branched-chain amino acids (BCAAs)—leucine, isoleucine and valine—plus other amino acids, glutamine and arginine, which together may have an impact on muscle building.^11,12 A comparison study on soy and whey proteins in recreationally trained young women found soy consumption, but not whey intake, increased preexercise serum antioxidant status while decreasing post exercise blood levels of peroxides and creatine kinase—toxins produced through oxidative stress.¹³

Somewhat contrary results were observed in another study where researchers concluded that (on an acute basis), a significant increase in serum antioxidant capacity was not detected following consumption of soy protein (five methods of assessment were used); however, significant differences were observed between soy with trace isoflavones and a milk protein group,¹⁴ reaffirming soy’s advantage in quenching free radicals.

Soy and whey went “mano y mano” in the human clinical arena in a recent study out of the Indiana University School of Medicine, Evansville, with researchers finding soy and whey protein in the skeletal muscle of exercised rats synthesize protein at comparable measures after strenuous exercise.¹⁵ Rats were given either carbohydrates only (C), carbohydrates and soy protein (CS), or carbohydrates and whey protein (CW)—one hour after a nearly 2.5-hour treadmill run. An hour later, the degree of muscle protein synthesis was measured in each rat and compared to control. Insulin and BCAA concentrations were higher in the CS and CW groups, with serum leucine and isoleucine the highest in the CW group. Compared with the carbohydrate group, both the carbohydrate/soy group and carbohydrate/whey group increased protein synthesis in skeletal muscle. “Taken in total, our study suggests both soy and whey proteins are useful sources of protein for muscle support following aerobic exercise,” said the researchers.

Another study confirmed supplementing with either a soy or whey protein increased lean tissue mass and strength when taken during resistance training.¹⁶ In the double blind study, 27 untrained healthy subjects (18 female, 9 male) ages 18 to 35 years were randomly assigned to take either whey protein (1.2 g/kg body mass whey protein + 0.3 g/kg body mass sucrose power), soy protein (1.2 g/kg body mass soy protein + 0.3 g/kg body mass sucrose powder) or placebo for six weeks. Measurements for lean tissue mass (using dual energy X-ray absorptiometry), strength (1- repetition maximum [RM] for bench press and hack squat), and also an indicator of myofibrillar protein catabolism measurements were taken before and after training.

There are differences in how the various dietary proteins affect whole body protein anabolism, as male bodybuilders achieved a significantly greater gain from whey than casein in a double blind study examining the effects of supplementation with two proteins, hydrolyzed whey isolate (WI) and casein (C).¹⁷ Strength, body composition and plasma glutamine levels were measured in the 10-week, supervised resistance training program on recreational bodybuilders supplementing normal diet with either whey or casein. Strength was assessed by one RM in three exercises (barbell bench press, squat and cable pull-down); body composition was assessed, and plasma glutamine levels were determined the week before and the week following the 10th week of training. Plasma glutamine levels did not change in either group and the whey group achieved a significantly greater gain in lean mass than the casein group and a significant decrease in fat mass compared to the casein group. Those taking whey also achieved significantly greater improvements in strength compared to the casein group in each exercise. And researchers found, when strength changes were expressed relative to body weight, the whey group still achieved significantly greater improvements in strength compared to casein.

Another tag-team, creatine and whey, in various combinations improved strength and muscle hypertrophy in trained men, but results varied in body types.¹⁸

A double blind, randomized trial out of the American College of Sports Medicine, Indianapolis, reported 76 percent of strength improvement could be attributed to hypertrophy of muscle in resistance-trained males. Participants were matched for strength and placed into one of four groups taking 1.5 g/kg body weight per day of one combination, either: creatine/carbohydrate (CrCHO), creatine/whey protein (CrWP), whey protein (WP) only, or carbohydrate only (CHO). Several assessments were completed the week before and after an 11-week structured, supervised resistance exercise (RE) program and included strength (1RM; three exercises), body composition (DEXA), and vastus lateralis muscle biopsies for determination of muscle fiber type (I, IIa or IIx), cross-sectional area (CSA), contractile protein and creatine content.

And researchers from McMaster University in Ontario examined how dairy-derived protein affected the process of muscle protein synthesis and muscle protein breakdown after resistance exercise.¹⁹ Using models of skeletal muscle amino acid turnover, researchers followed young men through 12 weeks of resistance training and observed a tendency for greater gains in whole body lean mass and protein deposition in skeletal muscle with milk protein consumption, even when the quantities of energy and protein were balanced.

Creatine (from Kreas, Greek, meaning flesh) is a nitrogenous organic acid that helps supply energy to muscle cells as it is converted to phosphocreatine (PCr), an energy source treasured by athletes requiring high intensity energy bursts. Because of this, creatine has been combined with magnesium for synergistic support of adenosine triphosphate (ATP) production. One study confirmed a creatinemagnesium chelate (as Creatine MagnaPower™, Albion Advanced Nutrition) more effectively enhanced the generation and regeneration of ATP for muscular performance, compared to supplementation with creatine monohydrate, creatine monohydrate plus magnesium oxide, creatine monohydrate plus magnesium amino acid chelate, or placebo.²⁰ Further study revealed creatine-magnesium chelate supplementation may allow runners to reach their physiological threshold later in exercise, according to researchers from Western Washington University.²¹ Most recently, creatine has demonstrated benefit to seniors who experience enhanced strength and lean mass gains after taking the supplement during a strength training program.²²

Norway gives us a cutting edge sports ingredient derived from preembryonic fertilized hen eggs, young tissue extract (YTE). It’s known for its ability to optimize certain hormone levels in the body, including testosterone and cortisol—which may explain its benefits to weight management. In a single blind, placebo-controlled pilot study conducted at University of Denver, six weeks of supplementation with either YTE (2.8 g/d) plus creatine or creatine alone in healthy, physically active subjects showed a trend toward increased fat reduction and increased muscle mass in the YTE-creatine group.²³ There were more significant results in a Norwegian study, where advanced bodybuilders demonstrated a meal containing 111 g YTE resulted in increased cellular uptake of testosterone and insulin— which can promote lean muscle mass—while decreasing cortisol, a stress hormone that promotes abdominal weight gain.²⁴

Arginine (especially L-arginine) is one of the 20 most common natural amino acids, and offers several benefits to sports enthusiasts, including increased skeletal muscle glucose clearance,²⁵ increased anaerobic work capacity and muscle mass catalyzed by resistance training,²⁶ decreased levels of exercise-induced waste products in the blood,²⁷ and increased endurance.²⁸

But the most abundant amino acid in the body is glutamine. It is converted to glucose during exertion, providing fuel for the musculoskeletal and immune systems. Trials have demonstrated glutamine supplementation may reduce the incidence of illness in endurance athletes at high risk of infection due to rigorous, prolonged exercise.^29,30

Gain More Lean

While building muscle is important, losing fat at the same time helps to streamline the body, increase body strength and peak performance. Protein returns to the weight room with this very goal. Consider a critical view supported by the National Institutes of Health (NIH), published in the Journal of American College of Nutrition. Researchers found higher-protein diets may significantly increase weight loss and possibly percentage of fat lost when compared to a lower protein diet in the short term.³¹ This may be caused by increased satiety and decreased energy intake with a higher-protein diet. The market has responded to the news, as a variety of whey-based energy foods including high-protein frozen juice bars, ready-to-drink beverages (geared towards faster uptake of amino acids), meal replacement bars and more are copiously available to consumers.

Protein’s role appears linked to satiety, the rmogenesis and body composition.³² Danish researchers found overweight and obese individuals following a high protein diet had significantly greater weight loss than those on a medium protein diet after six months.³³ At the 12-month follow up, there was equal weight loss between groups, but the high protein subjects had a greater reduction in abdominal fat; both groups maintained their weight loss for 24 months. And a research review from the University of Illinois Urbana-Champaign noted part of the benefit of a higher protein diet for weight loss may be due in part to increased intake of BCAAs because they help regulate muscle protein synthesis and glycemic control.³⁴

In terms of weight loss, thermogenesis, the generation or production of heat, is central to the benefits of the dehydroepiandrosterone (DHEA) metabolite 3-acetyl-7- oxodehydroepiandrosterone, also known as 7- oxo - DhEA. In one double blind, placebocontrolled trial, 30 obese subjects took either 100 mg/d 7-oxo- DHEA (as 7-Keto®, from Humanetics Corp.) or placebo twice daily.³⁵ Those taking 7-Keto showed significantly increased weight loss and three times more fat reduction than those taking placebo. Confirming its thermogenic effect on metabolism, a 2005 trial found 7-Keto administered to overweight adults in conjunction with a calorie-restricted diet could mitigate the decline in resting metabolic rate (RMR) normally associated with dieting.³⁶ Results specifically showed the 7-Keto and diet regimen led to a RMR increase of 1.4 percent, compared to a 3.9-percent RMR decline in control subjects. Researchers noted 7-Keto achieves thermogenesis by upregulating the activity of fat-burning enzymes, as opposed to acting as a stimulant. Other research has shown obese patients given a formula containing 7-Keto— plus L-tyrosine, asparagus root extract, choline, inositol, copper, manganese and potassium—for eight weeks exhibited increased weight loss and BMI reduction.37 7-Keto was recently patented for modulating the basal metabolic rate and weight loss.

A botanical used by athletes for its thermogenic properties is bitter orange, or C itrus aurantium (CA). A study demonstrated supplementation with CA (as Advantra Z®, from Nutratech) led to an increased thermogenic response and a measurable increase in metabolic rate in lean men and women when consumed alone and in conjunction with nutrition bars.³⁸ The study was conducted by researchers from the McGill Nutrition and Food Science Center at the Royal Victoria Hospital in Montreal, Canada. And in another clinical trial demonstrating the ability of CA to increase metabolic rate without affecting blood pressure, used indirect calorimetry to assess whether CA increased metabolic rate.³⁹ Thermic response to Advantra Z was higher in men when taken without food, and higher in women when taken with a meal, possibly due to diminished sympathetic nervous system response to meals in females. Furthermore, researchers found CA had no effect on blood pressure.

Another botanical, forskolin (Coleus forskolhii), may also impact fat loss. Forskolin extract (as ForsLean®, Sabinsa Corp.), was demonstrated in a 12-week study to improve body composition while concurrently increasing bone mass and serum free testosterone levels in overweight and obese men.⁴⁰ A similar 12-week randomized, double blind, placebo-controlled study of 23 overweight women revealed individuals receiving forskolin (ForsLean) had decreased body mass and had less fatigue and hunger.⁴¹ Additionally, no clinically significant interactions were seen in metabolic markers, blood lipids, muscle and liver enzymes, electrolytes, red cells, white cells, hormones, heart rate or blood pressure. “These study results indicate ForsLean helps preserve lean body mass, improve body composition and mitigate weight gain in overweight females with no apparent side effects,” said Vladimir Badmaev, M.D., Ph.D., vice president of scientific and medical affairs, Sabinsa Corp.

L-Carnitine helps to promote a healthier body weight and lean tissue deposition.^42,43,44 A number of studies have shown the beneficial effects of dietary L-carnitine for weight management in both animals and humans. One study found a shortage of L-carnitine in rats may increase food intake.⁴⁵ And carnitine combined with genistein appears to have anti-obesity effects, possibly by modulating certain genes. In one study, genistein with carnitine exerted anti-obesity effects in mice.⁴⁶ Mice fed high-fat diet alone had abdominal and back fat (relative to total body weight) were significantly higher compared with other mice groups fed normal diet; mice fed a high fat diet plus genistein, or high-fat diet plus genistein and L-carnitine—had lower weight gain compared to control.

And researchers from the University of Nottingham determined carnitine levels in skeletal muscles play an important role in the metabolism of carbohydrates and fats as fuel during exercise.⁴⁷ The study involved seven healthy, non-vegetarian young men with body mass indexes (BMIs) around 26, who received intravenous saline or carnitine; serum insulin was maintained at a physiologically high concentration during two randomized visits. Researchers measured skeletal muscle pyruvate dehydrogenase complex (PDC) activity and associated muscle metabolites. The combination of hypercarnitinemia and hyperinsulinemia increased muscle total carnitine content by 15 percent and was associated with decreases in both pyruvate dehydrogenase complex activity and muscle lactate content.

Researchers have also explored the benefits of fenugreek in this area. In a human clinical trial, conducted in-house, 60 healthy males between the ages of 18 to 35 years (and who had previously trained for resistance/power exercise for at least one month) were given 300 mg of the botanical fenugreek seed extract (as Testofen™, Gencor Pacific)—twice daily (morning and evening) for eight weeks. They were tested three times during the trial period; there was no significant change in the body weight after eight weeks of consumption of fenugreek extract, and BMI remained same, however, free testosterone levels increased significantly and reduction in skin fold thickness was significant in the thigh and biceps regions.

Conjugated linoleic acid (CLA), an omega-6 fatty acid, refers to a family of isomers of linoleic acid and is found primarily in the meat and dairy products of hoofed animals (sheep, lamb, beef, etc.) as well as safflower oil; CLA has been found to reduce body fat in humans,⁴⁸ particularly abdominal fat, as changes in serum total lipids and decreased whole body glucose uptake. The maximum reduction in body fat mass was achieved with a 3.4 g daily dose.⁴⁹ Some questions arise, however, as researchers from North Carolina State University, Raleigh, noted CLA’s mechanisms of action are still largely unknown, although it appears to modulate energy expenditure, fatty acid oxidation, lipolysis and lipogenesis.⁵⁰

The bulk of studies have been more positive. A randomized, placebo-controlled, double blind study conducted at the University of Wisconsin, Madison, found CLA reduced weight.⁵¹ Forty healthy overweight men and women were given 4 g/d of CLA (Tonalin®, from Cognis Nutrition & Health) for eight months. Those on the active intervention reduced their body fat mass by 2.2 pounds and body weight by 1.3 pounds, while those on the placebo gained 1.5 pounds of body fat mass and 2.4 pounds of body weight. The researchers concluded Tonalin safely reduces body fat mass, maintains lean body mass and aids in weight management for aging overweight adults. Long-term benefits were supported by a two-year study published in the Journal of Nutrition concluded that long-term supplementation with conjugated linoleic acid (as Tonalin) confirmed taking CLA decreases body fat mass and maintains lean body mass, aiding weight management.⁵² Studies have shown CLA may reduce fat tissue deposition and body fat mass without an attendant decrease in lean body mass or changes in diet,⁵³ and CLA caused reductions in body fat mass (BFM) and increases in lean body mass (LBM) by as much as 9 percent.⁵⁴ 

Antioxidants vs. Antiheroes

Low levels of antioxidants or inhibition of antioxidant enzymes causes oxidative stress and may damage or kill cells, the workout nemesis. The dark side to intense exercise is that the accumulation of toxins causes oxidative damage and decreased immunity, specifically due to decreased helper/suppressor T-cell ratio, salivary levels of immunoglobulin-A, lymphocyte proliferative response and natural killer cell activity; and elevation of stress hormones.⁵⁵ Both prolonged steady-state exercise and high-intensity bursts of energy overwhelm the body’s capacity to detoxify reactive oxygen species (ROS), which can damage cell structures.⁵⁶ One way to counteract oxidative damage is through intake of antioxidant vitamins and minerals, which inhibit oxidative stress to organs, muscles, blood and other areas of the body.⁵⁷

Astaxanthin, a carotenoid classified as a xanthophyll, is a biological antioxidant with many highly potent pharmacological capabilities, such as antioxidative activity,^58,59 anti-tumor and anticancer effects,⁶⁰ immunomodulating actions^61,62 and anti-diabetic⁶³ and anti-inflammatory action.^64,65 There are strong indications that astaxanthin supplementation protects muscle tissue against free radical oxidative damage during exercise and also inhibits the secondary inflammatory response,^66,67 leading to increased muscle endurance.

A recent study out of Tokyo found mice given oral astaxanthin (AstaREAL 50F, Fuji Chemical Industry Co.) in 1.2, 6 or 30 mg body weight by stomach intubation for five weeks improved swimming endurance.⁶⁸ Those given astaxanthin had a significant increase in swimming time to exhaustion as compared to the control group. Blood lactate concentration in the astaxanthin groups was significantly lower than in the control group and plasma non-esterfied fatty acid (NEFA) and plasma glucose decreased by swimming exercise in the control group, whereas in the astaxanthin group, NEFA and plasma glucose were significantly higher. Astaxanthin also significantly decreased fat accumulation—suggesting the improvement in swimming endurance is caused by an increase in utilization of fatty acids as an energy source.

In a double blind study, scientists from an independent research group administered astaxanthin (as BioAstin®, Cyanotech) or placebo to 23 individuals for 56 days.⁶⁹ Supplementation with astaxanthin reduced systemic inflammation (as measured by levels of C-reactive protein [CRP] in blood serum) by more than 20 percent. Placebo did not reduce CRP levels; and there was a statistically significant difference between the two treatments, suggesting astaxanthin may significantly reduce CRP scores.

The antioxidant activity of tea-derived catechins has been extensively studied, and green tea extract intake is associated with increased weight loss due to diet-induced thermogenesis, generally attributed to the catechin epigallocatechin gallate (EGCG).⁷⁰ A possible explanation for why green tea is effective in stimulating thermogenesis is ihibition of the enzyme that degrades norepinephrine.⁷¹ According to a review conducted in 2006 by Novartis Institutes for BioMedical Research, although green tea demonstrated strong antioxidative, anti-inflammatory and anti-cancerous properties, there is some discrepancy between the results from human epidemiological studies and cultured cell and animal models, possibly due to metabolism and/or bioavailability.⁷²

And a recent study demonstrated another bonus from green tea—endurance improvement, mediated, at least partly, by increased metabolic capacity and utilization of fatty acid as a source of energy in skeletal muscle during exercise.⁷³ The mouse study showed running times to exhaustion in mice fed 0.5 percent GTE were 30-percent higher than control and were accompanied by a lower respiratory exchange ratio, higher muscle beta-oxidation activity, and lower malonyl-CoA content. In addition, muscle glycogen content was high in the GTE group compared with control.

Strenuous exercise abruptly increases oxygen consumption thus aggravating oxidative stress and generating free radicals. In healthy individuals, the antioxidant system defends tissues against free radical attack, and superoxide dismutase (SOD) is one of the major players. In a four-week administration of the oral SOD (GliSODen®, P.L. Thomas), a significant change in oxidative status and a significant decrease in exercise-induced lactate release was observed.⁷⁴

Physically-active individuals can benefit from two vitamin antioxidants—vitamin E and vitamin C. For immunity, vitamin E may substantially increase circulating neutrophils in physically active individuals who have sustained oxidative damage to muscles caused by eccentric bouts of exercise.⁷⁵

During endurance exercise, oxygen consumption by the skeletal muscle can increase 100-200 times.⁷⁶ A randomized, double-blind study in 22 runners (half were female) participating in an annual ultramarathon race, both vitamins E and C prevented increases in lipid peroxidation, but had no apparent effect on DNA damage, inflammation or muscle damage,⁷⁷ suggesting the mechanism of oxidative damage is operating independently of the inflammatory and muscle damage responses.

Decreased oxidative damage to another group of runners taking vitamins E and C prevented endurance exercise-induced lipid peroxidation without affecting inflammatory markers.

Vitamin E inhibits oxidative stress in athletes through suppression of low-density lipoprotein (LDL) cholesterol oxidation associated with strenuous endurance exercise, according to a review out of Tokyo Medical University.⁷⁸

Vitamin C is implicated in a number of biochemical pathways important to exercise metabolism and health in active individuals.⁷⁹ A placebo-controlled study in Spain found vitamin C supplementation of volunteer endurance athletes participating in a duathlon competition increased erythrocyte antioxidant enzymes and plasma antioxidant levels during athletic competition and short-term recovery, while athletes given placebo experienced increases in serum markers of oxidative stress, including uric acid and lactate dehydrogenase.⁸⁰ The researchers concluded vitamin C supplementation defends against oxidative stress and prevents negative exercise-related effects on erythrocyte integrity. And a Taiwanese study linked insufficient vitamin C status to low serum concentrations of lipid peroxides and increased muscle damage in female weightlifters undergoing intensive resistance training.

Vim and Vigor

Heracles would be proud, as enhancing testosterone and increasing energy can mean the difference in getting from a ‘just get through it’ to a ‘let’s get thorough’ workout. Among the botanical bench pressers believed to benefit athletic potential—mostly by increasing energy and protecting tissues against damage—is French maritime pine bark extract. In a California State University study, 24 recreational athletes received either 200 mg/d French maritime pine bark extract (as Pycnogenol®, from Natural Health Science) or placebo for one month in a double blind, crossover design.⁸² Composite endurance scores for two groups of individuals given pine bark extract increased by a statistically significant 21 percent compared to placebo. Researchers out of Germany proposed the oligomeric fraction of pine bark extract also has the potential to exhibit local effects in the gastrointestinal tract by inhibiting a-glucosidase, thereby contributing to improved glycemic control.⁸³ The study analyzed the inhibitory activity of Pycnogenol, green tea extract and acarbose towards a-glucosidas, discovering pine bark extract exhibited the highest inhibitory activity on a-glucosidase.

Eurycoma longifolia (tongkat ali) has become popular for its testosterone-enhancing properties; because of that, it is included in certain herbal supplements for bodybuilders. An unpublished, placebo-controlled study presented at the 3rd annual International Society of Sports Nutrition Conference demonstrated Tongkat ali (as ActivAli™, SourceOne) safely enhanced testosterone while simultaneously lowering cortisol levels—boding well not only for athletes but for dieters alike. Participants were given either ActivAli or placebo approximately 30 minutes prior to a 24-hour endurance mountain bike race. Cortisol levels in the ActivAli group were 33-percent lower than in the placebo group. “This new science holds significant potential for the sports nutrition, metabolic syndrome and weight loss markets,” said James Roza, co-author of the study and vice president of business development, technology and science for SourceOne.

Guarana is nature’s stimulant—used as an ingredient in energy drinks and as a dietary supplement to promote health and weight loss. Guarana originates from northern Brazil and contains numerous phytochemicals. Brazilian scientists studying the difference between caffeinated and decaffeinated guarana found the whole herb extract led to lower serum lactate levels and higher muscle glycogen content in both trained and untrained rats.⁸⁴ They reported guarana’s positive effect on lipid metabolism was negated by decaffeination. A previous study from Japan, found water extract of guarana (500 mg/kg) increased blood glucose levels, decreased liver glycogen content and significantly suppressed exercise-induced hypoglycemia in mice within 60 minutes of oral maltose administration.⁸⁵

A study out of Queensland, Australia, recently assessed the knowledge, prevalence and quantity of caffeine use by athletes competing at the 2005 Ironman Triathlon World Championships, finding the majority of athletes (89 percent) planned on using a caffeinated substance immediately prior to or throughout a race.⁸⁶ And caffeine (equal to approximately two cups of brewed coffee) created a large reduction in pain resulting from eccentric exercise-induced, delayed-onset muscle injury in another study.⁸⁷ Researchers out of the Department of Kinesiology, University of Georgia, Athens conducted a double blind, placebo-controlled, repeated-measures experiment examining the effects of a 5 mg kg(-1) body weight dose of caffeine on delayed-onset muscle pain intensity and force loss in response to 64 eccentric actions of the quadriceps (induced by electrical stimulation). Pain intensity was then measured using a 0 to 100 visual analog scale; caffeine produced a large, statistically significant decreased pain sense during the maximal voluntary isometric contractions (MVIC), while the reduction in pain scores during submaximal voluntary eccentric movements was smaller as was the increase in MVIC force.

Endurance, Skipping the Shortcut

Several ingredients play a part in endurance, giving the runner, for example, that extra mile—taking the long way home, pushing farther and faster without looking back—as the goddess of victory looks on.

From Peru, the cruciferous plant Lepidium meyenii, or maca, is found in a variety of commercial products. It has gained attention as a dietary supplement, with claims of anabolic and aphrodisiac effects. For women, supplementing with maca root may reduce bone loss caused by estrogen deficiency in menopause,⁸⁸ In another study a proprietary aqueous extract (MacaPure®, Naturex) increased energy and endurance, as well as enhance sexual potency.⁸⁹

Adaptogenic compounds also have a role to play. Belgian researchers found the adaptogen Rhodiola rosea improved endurance exercise capacity in young healthy volunteers.⁹⁰ This study supports previous animal research which showed that rhodiola extract increases the synthesis or re-synthesis of ATP in mitochondria, and stimulates energetic recovery processes after intensive muscular work.⁹¹ Based on fragmentary research data, a number of beneficial effects have been attributed to the intake of Rhodiola rosea root extracts. These include enhancement of physical work performance,⁹² increased muscle strength,⁹³ suppression of mental fatigue,^94,95 and prevention of high altitude sickness.⁹⁶

Another botanical shown to improve endurance, fenugreek seed extract (FG), assisted in improvement in swimming endurance in male mice due to increased utilization of fatty acids as an energy.⁹⁷ Mice were given 300 mg FG for four weeks. The 300 mg/kg FG group showed a significant increase in swimming time before exhaustion compared to control. In the FG groups, blood lactate concentration was significantly lower than in the control group. In the control group, plasma non-esterified fatty acid (NEFA) and plasma glucose were decreased by swimming exercise. But in the FG group, NEFA and plasma glucose were significantly increased by swimming. FG treatment also significantly decreased fat accumulation.

The depletion of endogenous carbohydrate stores (muscle and liver glycogen and blood glucose) contribute to fatigue during high-intensity exercise.^98,99 The fungal carbohydrases (as Carbogen™, Triarco) patented enzyme blend of amylase, cellulase, and hemicellulase, consumed with a meal replacement bar increased glucose metabolism and improved exercise performance in five male competitive cyclists.¹⁰⁰

Joint Health: Making the Bend

Achilles had his vulnerable heel, and human joints can wear down—impeding even the strongest athlete from his goal—as high impact or strenuous exercise can result in stiffness, pain, inflammation and loss of function in joints, tendons, ligaments and other cartilaginous areas within the body. Specifically in athletes, the connective tissue of the knee is frequently injured, especially in those involved in contact sports.^101,102

When it comes to at risk knees and joints, glucosamine and chondroitin are power duo proteins responsible for elasticity in cartilage. As exemplified in a recent horse study out of Lexington, Ky., which found consistent use of oral glucosamine/chondroitin resulted in decreased need for intra-articular distal tarsal joint injections to maintain soundness in a group of show hunters/jumpers.¹⁰³ Martha Rodgers VMD, in conducting the eight-year study on 10 horses, found glucosamine/chondroitin (10 g/d, as GLC 5500, GLC), notably dropped the need for injections even after five to eight months (from 1.7 injections per year prior to supplementation to 0.85 injections per year after).

In research involving exercise-induced knee cartilage injuries, about 88 percent of subjects taking glucosamine experienced some degree of pain relief and improved joint mobility, in a study out of Australia.¹⁰⁴ Similarly, subjects with symptomatic knee osteoarthritis who were given chondroitin sulfate reported a decrease in joint pain and an increase in range of motion;¹⁰⁵ radiological progression revealed significantly decreased width in the medial femoro-tibial joint space on weight-bearing X-rays of both knees. And, oral supplements of glucosamine do not appear to impact insulin function or endothelial health in lean or obese subjects.¹⁰⁶ Studied in combination as a part of the Glucosamine/chondroitin Arthritis

SportS NutritioN SportS NutritioN

Intervention Trial (GAIT), glucosamine and chondroitin supplementation was also more effective in relieving severe knee pain to some degree in almost 80 percent of subjects with knee pain.¹⁰⁷ Also, the Glucosamine Unum In Die Efficacy (GUIDE) study, which compared glucosamine to acetaminophen, revealed glucosamine sulfate helped reduce scores on various osteoarthritis symptom indices.¹⁰⁸ Combined with undenatured collagen type II (as UC-II®, from InterHealth), the glucosamine and chondroitin combination better improved joint pain and lameness in dogs than did glucosamine-chondroitin alone.¹⁰⁹

Rebuild, Renew For Another day

At the molecular level, stimulating protein synthesis and minimizing protein breakdown are the processes essential to efficient recovery after exercise.¹¹⁰ Getting to the next workout in optimal health requires recovery—including proteins, isoflavones, botanicals and vitamins. Isoflavones may help restore the altered redox homeostasis of antioxidant enzymes following exercise.¹¹¹ Redox homeostasis is a group of processes critical to cell function and prevention of severe cellular damage. Damaging free radicals generated in biological processes such as aerobic exercise may change the cellular redox status, leading to oxidative stress and disruption of redox homeostasis.

Maintaining a strong immune system is one way to minimize injury. Proteins and amino acids contribute positive effects on immune health, which can be compromised by strenuous, prolonged exercise that depletes the body. In athletes exposed to exerciserelated weakened immunity, whey protein has boosted immune response.^112,113 Similarly, triathletes and long distance runners taking supplemental branched chain amino acids, which are abundant in whey, restored peripheral blood mononuclear cells proliferation in response to mitogens and modified the pattern of cytokine production, encouraging a “Th1 type” immune response following a prolonged, intense bout of exercise.¹¹⁴

In a recent review conducted by Poeckel and colleagues, experimental data from animal models and studies with humans confirmed the potential of oleogum resins from the botanical boswellia (Boswellia serrata) extracts for the treatment of inflammation.¹¹⁵

And findings by Volek and colleagues found a role for L-carnitine apart from its classical muscle energetic function: daily L-carnitine consumption prior to high intensity exercise significantly reduced muscle soreness and decreased muscle damage in healthy subjects.^116,117 Similarly, in healthy subjects, L-carnitine significantly improved the mean power output and resulted in a better recovery after strenuous exercise.¹¹⁸ The protective effects might be partly due to enhancement of oxygen supply to the muscle via increased blood flow.¹¹⁹ In a study conducted out of the Department of Kinesiology, University of Connecticut, Storrs, L-Carnitine L-tartrate (as L-Carnipure, Lonza) upregulated androgen response (AR) content, which may promote recovery from resistance exercise.¹²⁰

Tribulus terrestris targets increasing the body’s natural testosterone levels— thereby helping to build muscle and improve male sexual performance. In weight lifting, tribulus supplements are often used as post cycle therapy used in order to restore the body’s natural testosterone levels. Along with its clinically proven aphrodisiac properties,^121,122,123tribulus, through inhibiting the activity of aglucosidase in the small intestines, significantly slowed the increase in postprandial blood glucose levels in rats,¹²⁴ having a hypoglycemic effect.^125.

Zinc, magnesium and vitamin B6 are essential nutrients used by strength athletes such as bodybuilders to replenish lost nutrients. All three of these compounds are important in biological processes, yet less than 50 percent of Americans get enough magnesium.¹²⁶ According to USDA researchers, when exercise enhanced mineral losses are coupled with inadequate dietary intakes, athletes are at special risk to mineral deficiencies.¹²⁷ A novel zinc and magnesium formulation consisting of covalently-bound zinc-magnesium aspartate and vitamin B6 (as ZMA®, InterHealth Nutraceuticals Corp.) increased free testosterone and enhanced muscle strength in trained athletes significantly greater than placebo.¹²⁸

The days of Milo may long gone, but the spirit of the sport remains in the arena—be-it a track or treadmill, back road or weight room, today’s weekend warrior vies for position—where fat ends and muscle begins. With the right ingredients these athletes can attain the strength and stamina, while improving immunity and decreasing oxidative damage, to do even the Parthenon proud.

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