Sports Nutrition

Ashwagandha and Terminalia arjuna May be Safe and Natural Alternatives to Enhance Athletic Performance and Endurance

Numerous Ayurvedic herbs have been clinically tested regarding performance enhancement, post-workout recovery time, and prevention of muscle damage. Performance enhancement property of Ayurvedic herbal extracts is due in part to their antioxidant potency and their century-long traditional use as effective drugs to treat human ailments across a broad-spectrum of afflictions.

Physical activity and exercise is one of the main wellsprings of health and well-being. Exercise can stimulate our immune system and provide us with vitality, strength, and stimulate the natural healing mechanisms of the body. In society, enormous sums of money are spent on attending athletic events and a great deal of research has been conducted on our athletes regarding performance enhancement using natural compounds.

Ayurvedic herbs provide a wide spectrum of benefits, from potent antioxidant capacity to protecting tissues and muscles against free radical damage provoked by intense exercise. Regular exercise reduces inflammatory signaling molecules, including INF-γ, TNF-α, and IL-6. Exercise also stimulates DNA repair through a hormesis-like mechanism, where a tiny amount of DNA damage produces a massive over-response in DNA repair mechanisms and over-expression of endogenous antioxidant enzymes that include superoxide dismutase, catalase, and glutathione peroxidase. The Antioxidant Response Element (ARE) is exquisitely sensitive to changes in free-radical levels caused by exercise and orders the production of these enzymes when needed to maintain cellular homeostasis. The anti-inflammatory effect of exercise specifically protects the cardiovascular system by reducing adhesion molecules that could otherwise cause blood clots, while also lowering C-reactive protein and homocystine levels, biomarkers associated with lower cardiovascular disease risk.

Following are a few natural ingredients that are considered useful as sports nutrients:

Ashwagandha

Ashwagandha, also known as Withania somnifera or Indian winter cherry, has been an important traditional herbal medicine for over 3,000 years. It is an integral part of several formulations meant for a variety of musculoskeletal conditions (e.g., arthritis, rheumatism), and as a general tonic to increase energy, improve overall health and longevity.

In an 8-week, double-blind, placebo-controlled trial, 57 young men with no prior experience with resistance training were randomized into a treatment group of 29 persons and a placebo group of 28. Subjects in the treatment group consumed 300 mg of Ashwagandha extract twice daily, while the control group took a starch placebo. Both groups underwent resistance training for 8 weeks and measurements were made at the end of week 8. The primary efficacy measure was muscle strength and secondary measures were muscle size, body composition, serum testosterone, and muscle recovery time. Muscle recovery was evaluated using serum creatine kinase levels as a marker of post-exercise muscle injury.

The Ashwagandha-treated group had greater increase in muscle strength on the bench-press exercise (46. 0 kg vs. control 26.4 kg) and the leg-extension exercise (14.5 kg vs. control 9.8 kg), greater muscle size increase of the arms (8.6 cm vs. control 5.3 cm), and chest (3.3 cm vs control 2.0 cm). The subjects receiving Ashwagandha also experienced a greater reduction of exercise-induced muscle damage as seen byt he higher stabilization of serum creatine kinase levels (higher is better) (i.e. 1,462.6 micromol/ liter vs. the placebo group 1,307.5 micromol/liter).The Ashwagandha-treated group had higher testosterone levels at the end of 8 weeks (Ashwagandha group 96.2 ng/dl vs. placebo group 18.0 ng/dl), along with a greater decrease in body fat percentage.

The most striking observation of the study was increased levels of testosterone in the Ashwagonda-treated group (from 18.0 to 96.2 ng/dl). This level had previously been seen only in the Indian (brown variety) of Fenugreek extract-treated men with 98% testosterone increase compared to a placebo group after six weeks of weight training.

Terminalia arjuna

This Ayurvedic herb is commonly known by the name Arjuna, and is a powerful heart tonic that is commonly used in various Ayurvedic preparations by traditional Ayurvedic practitioners to support cardiovascular health. It is known to increase the energy potential of the body due to the ability to increase the rate of oxygen consumption by cells.

Effects of Ashwagandha and Terminalia arjuna extracts on Exercise Performance

A clinical trial involving 40 normal, healthy young people of both sexes were divided into 4 groups: the first group receiving a standardized extract of Ashwagandha 500 mg, the second group receiving a standardized extract of Terminalia arjuna bark extract 500 mg, and a third group receiving both Ashwagandha and Terminalia arjuna extracts, 500 mg of each. The fourth group received placebo capsules. All the subjects continued the regimen for 8 weeks.

The Ashwagandha-treated group had increased velocity (breathing power) and VO2 max (lung oxygen capacity) increases over the placebo group during exercise. The Terminalia arjuna group had increased VO2 max and lowered resting systolic blood pressure. In the Ashwagandha and Terminalia arjuna-treated group, the improvement was seen in both VO2 and lower post-exercise diastolic and systolic blood pressure. The lowering of post exercise blood pressure signifies better recovery and healthier blood pressure. The study author concluded that “Withania somnifera (Ashwagandha) may therefore be useful for generalized weakness and to improve speed and lower limb muscular strength, and neuromuscular coordination. Terminalia arjuna may prove useful to improve cardiovascular endurance and lowering systolic blood pressure. Both drugs appear to be safe for young adults when given for mentioned dosage and duration.”

Ayurvedic herbs have been mostly overlooked regarding their applications in the performance enhancement field. Recent human clinical trials have revealed the potency of Ashwagandha and Terminalia arjuna extracts in increasing weight training results, cardiovascular risk reduction in exercise, increased lung oxygen capacity, and lower resting blood pressure effects. Hence, Ayurvedic herbs should be re-examined by both consumers and supplement formulators as novel ingredients to include in exercise-based products.

Sports nutrition is a constantly evolving field – we understand it better because of the outpouring of results from thousands of research studies that are conducted annually.  Finding sports nutrition products and ingredients that have proven studies to support claims of performance enhancement and energy in this field can be challenging, as unsubstantiated claims typically cloud the marketplace. We will list and discuss products in this review that have human clinical trial data at improving energy, endurance and other sports nutrition goals.

Sports nutrition supplements typically contain carbohydrates, fats, proteins, vitamins, minerals, herbs, and sometimes plant extracts. Supplements can generally be classified as convenience supplements such as ready to drink supplements, energy bars and meal replacement powders. They provide a convenient means of meeting caloric needs, while also delivering performance enhancement supplements.

Performance enhancement supplements that have science behind them include ergogenic agents such as caffeine, guarana, creatine, green tea extracts, willow bark, Kola nut, Sida cordifolia, Citrus aurantium (bitter orange), calcium and sodium phosphate, thyroid stimulators, including guggulsterones, black pepper extracts, and ginger root.

Plant-based supplements that are used in formulations include Tribulus terrestris (puncture weed or caltrops) and Fenugreek seed extract (Trigonella foenum-graecum), extracts that stimulate the natural production or release of bound testosterone to free testosterone. Free testosterone is the only metabolically active form of testosterone.

Both Tribulus and Fenugreek seed extracts have been marketed to promote greater gains in strength and muscle mass during weight training with sufficient clinical trial data to prove their efficacy.

Dietary calcium has been shown to suppress fat metabolism and weight gain during periods of high caloric intake. Further, increasing calcium intake has been shown to increase fat metabolism and preserve thermogenesis during caloric restriction.

The role of sodium and calcium phosphate on energy metabolism and exercise performance has been studied over several decades of research. Phosphate supplementation may influence metabolic rate possibly by affecting thyroid hormone levels. Phosphates could serve as potential thermogenic nutrients in supplement formulations.

Phosphates are formed during the Krebs cycle for energy production. Each turn of the Krebs or Citric acid cycle generates one guanosine triphosphate molecule which has a high-energy phosphate bond, stored energy that can then be broken to release energy for the cell.

Other Krebs cycle intermediates that have been used in sports nutrition include creatine phosphate, alpha-keto glutarate (AKG), sodium pyruvate and ethyl pyruvate. Creatine supplementation has, by far, the largest clinical trial documentation at increasing energy and enhancing athletic performance, although there is evidence that it loses its efficacy after long term use.

Green tea is believed to increase energy expenditure by stimulating brown fat (adipose) tissue thermogenesis. Green tea supplementation in combination with caffeine increased 24-hour energy expenditure and fat utilization in humans. The thermogenic effects of green tea supplementation depend on the synergistic effects of the caffeine and EGCG (epigallocatechin gallate) contents.

Other reported sports nutrition extracts include Rhodiola rosea, Eleutherococcus senticosus (formerly called Siberian ginseng) and Schizandra chinensis (Schizandra dried berries or extracts). These are all classified as adaptogens, since they allow the plants that produce them to survive in the Siberian tundra, where freezing and drought conditions occur on a regular basis.

These extracts are also called Russian adaptogens. The clinical trial data was compiled by Russian scientists beginning in 1947 through the 1970’s, but Western clinical double-blind or placebo-controlled standards were not used, which makes the data obtained from the studies of questionable value.

Schizandra chinensis does have the most compelling clinical data – it acts as a central nervous system stimulant or ergogenic agent. The effects after two months of use diminish, according to some of the Russian studies.

Forskolin is a plant native to India that has been used for centuries in traditional Ayurvedic medicine primarily to treat skin disorders and respiratory problems. A considerable amount of research has evaluated the physiological and potential medical applications of Forskolin over the past 25 years. Forskolin has been reported to increase cyclic AMP and thereby stimulate fat metabolism and is used in some sports nutrition formulas.

St. John’s Wart, Kava, Ginkgo Biloba, Ginseng, and L-Tyrosine are believed to serve as naturally occurring antidepressants, relaxants, and mental stimulants and are often included in sports nutrition formulas.

Garcinia cambogia dried fruit rind contains between 10% to 50% Hydroxycitric Acid (HCA), a nutrient that increases fat oxidation by inhibiting citrate lyase and new fat cell formation (lipogenesis).

There is sufficient clinical trial data to support its inclusion in sports nutrition formulas, the calcium salt being the most metabolically active form of HCA.

New products are continually being introduced and marketed in the sports nutrition arena, which is rapidly growing because of health awareness and other factors. The consumer needs to be aware if the new or existing sports nutrition products are based on human clinical data to support their energy or performance enhancement claims.