Natural products and the athlete: facts and folklore

Ginseng does not enhance psychological well-being in healthy, young adults: results of a double-blind, placebo-controlled, randomized clinical trial

OBJECTIVE

Ginseng is a popular, commercially available dietary supplement that is purported to have a number of psychological benefits. The purpose of this study was to examine these claims, with specific reference to ginseng's effects on affect and mood.

DESIGN

Prospective, double-blind, placebo-controlled, randomized clinical trial.

PARTICIPANTS/SETTING

Eighty-three adults (40 women, 43 men) participated in this study (mean age = 25.7 year). Participants were recruited from within a university community and at area health clubs.

INTERVENTION

Participants were randomly assigned to one of three experimental conditions: placebo (lactose), 200 mg ginseng, or 400 mg ginseng. The ginseng preparation used in this study consisted of the Panax ginseng C A Meyer concentrate G115 in capsular format. Each participant was given a 60-day allotment of their respective supplement along with written instructions about the proper intake and storage of the capsules during the 8-week study period.

MAIN OUTCOME MEASURES

Positive affect, negative affect, and total mood disturbance. Measures were obtained pre- and post-intervention.

STATISTICAL ANALYSES PERFORMED

Repeated measures multivariate analysis of variance was used. Because there were three dependent variables, and in an effort to minimize the experimentwise-error rate, alpha was adjusted using the Bonferroni technique (i.e., P < .05/3 = P < .016).

RESULTS

Ginseng supplementation had no effect on positive affect, negative affect, or total mood disturbance (all P > .016).

CONCLUSION

The present findings do not support claims that chronic ginseng supplementation--at either its clinically recommended level or at twice that level--enhances affect or mood in healthy young adults.

Other ergogenic agents

Amid the surrounding chaos of the supplement blitz, athlete, coach, and physician alike must step back and place the issue of supplements into perspective. There is no legal supplement that can substantially alter performance to date in the same way as illegal drugs. Effectiveness, safety, legality, and purity of compounds are all issues that should be addressed when approaching the use of any supplement. Education about the validity of the claims of supplements is important. Research is lending useful and helpful information despite the many new products continually appearing on the market. Because there is no mechanism for investigations to adequately research every supplement, many of the supplements should be approached with caution and skepticism. In addition, supplements in and of themselves should not be viewed as the sole answer to performance improvement. There is some promise to an extremely small number of supplements that appear to enhance performance, yet they do so in the realm of complete athletic training, including hard work, sports-specific training and strength training, psychological preparedness, and good nutritional intake.

Search for the competitive edge: a history of dietary fads and supplements

The premise and promise of ergogenic aid use is rooted in antiquity and is based upon superstition and ritualistic behavior of athletes who perceive that past performances were predicated upon unique dietary constituents or dietary manipulation. Accounts from ancient times recommended that athletes and soldiers preparing for battle consume specific animal parts to confer agility, speed or strength associated with that animal. Scientific understanding of the chemical and physiological nature of muscular work in the early 20th century was followed by ergogenic aid use by athletes and rationalized as "scientific" justification. Ergogenic aids such as alkaline salts, caffeine, carbohydrate and protein have been used by athletes with variable success. As nutritionists and exercise physiologists discovered and perfected the scientific understanding of metabolic reactions, athletes in turn experimented with the amount, form and timing of administration in the search for optimal performance. Anabolic steroids and blood doping enhance athletic performance, but health risks, ethics and sportsmanship contravene their use. Popularity and use of ergogenic aids often have preceded scientific substantiation of claims. Current products such as protein isolates and antioxidant nutrients commonly are used by athletes, and many ergogenic aids available today differ little from those used long ago.

Effect of Eleutherococcus senticosus on submaximal and maximal exercise performance

We investigated the effect of Eleutherococcus senticosus Maxim L (ESML) on performance during submaximal and maximal aerobic exercise. Twenty highly trained distance runners randomly assigned in matched pairs to either an experimental (ESML) or placebo (PL) group, participated in an 8-wk double-blind study during which they completed five trails of a 10-min treadmill run at their 10 km (10K) race pace and a maximal treadmill test (T(max)). Following a baseline trail, ESML and PL consumed, respectively, 3.4 ml of ESML extract or placebo daily for 6 wk. Subjects were tested every 2 wk during supplementation and 2 wk following withdrawal. Heart rate (HR), oxygen consumption (VO2), expired minute volume (VE), ventilatory equivalent for oxygen (VE/VO2), respiratory exchange ratio (RER), and rating of perceived exertion (RPE) were measured during the 10K and T(max) tests. Resting, post-10K and post-T(max) blood samples were analyzed for serum lactate. No significant differences were observed between ESML and PL for: HR, VO2, VE, VE/VO2, RER, or RPE; T(max) time to exhaustion; or serum lactate. The data do not support an ergogenic effect of ESML supplementation on selected metabolic, performance, or psychologic parameters associated with submaximal and maximal aerobic exercise tasks.

Nutritional ergogenics in athletics

Nutritional ergogenic aids may be theorized to improve performance in athletics in a variety of ways, primarily by enhancing energy efficiency, energy control or energy production. Athletes have utilized almost every nutrient possible, ranging from amino acids to zinc, as well as numerous purported nutritional substances, such as ginseng, in attempts to enhance physical performance. This review focuses primarily on nutritional ergogenic aids thought to enhance performance by favourably affecting energy metabolism. Although most purported nutritional ergogenic aids have not been shown to enhance physical performance in well-trained, well-nourished athletes, some reliable scientific data support an ergogenic efficacy of several substances, including caffeine, creatine and sodium bicarbonate, but additional research is needed to evaluate their potential for enhancing performance in specific athletics events.