1. In a double-blind, placebo-controlled study, the effects of purified American ginseng extracts in two doses (8 mg/kg/bw and 16 mg/kg/bw, which equates to either 560 mg a day or 1120 mg a day for a 154-pound athlete) were studied. The protocol was as follows:
• control ride testing time to exhaustion, oxygen consumption, rate of perceived exertion and serum lactate levels.
• seven days of a placebo supplement followed by a second tested ride.
• seven days of ginseng followed by a third tested ride.
The second and third test rides both increased time to exhaustion when compared to the initial control ride. There were no measured differences between the second ride following placebo supplementation and the third ride following either high or low ginseng supplementation on the above mentioned factors. The authors concluded there was no ergogenic effect of ingesting a ginseng extract.1
2. In a second double-blind study, 28 men and women received either 200 mg of Panax ginseng extract or a placebo each day for three weeks. Workload, time to exhaustion and oxygen consumption were slightly higher in the ginseng group. The average serum lactate was slightly lower in the ginseng group. None of these numbers reached statistical significance. If they had, it would have indicated an ergogenic effect.
The average rate of perceived exertion (RPE) and heart rate (HR) were also slightly higher in the ginseng group, but again not statistically significant. If they (RPE and HR) had been, it would have indicated that ginseng had an ergolytic effect. The authors concluded that three weeks of ginseng supplementation did not enhance maximum exercise performance in young fit adults.2
3. In a third double-blind study, 11 men and women were given three gm of ginseng or a placebo. The protocol was as follows:
• initial run with measurements of HR, oxygen consumption, and time to exhaustion.
• seven days of placebo supplementation followed by a second measured run.
• a seven-day washout period followed by a third measured run.
• seven days of ginseng supplementation followed by a fourth measured run.
The only statistically significant difference in the entire study was an increase in the time to exhaustion following the third run (the run before subjects were given ginseng). The authors concluded that ginseng was ineffective at altering maximal aerobic performance.3
4. In an eight-week trial of eleutherococcus senticosus (ES), 20 men and women in a double-blind, placebo-controlled study were given either 60 drops (or 3.4 ml) of ES extract or a placebo. The subjects were tested every two weeks throughout the study and two weeks following the trial on both submaximal and maximal treadmill runs. There were no differences in lactic acid, HR, VO2 max or time to exhaustion between ginseng and placebo groups.
In a debriefing post-trial questionnaire, the subjects rated supplements on a scale that included three points for no effect and four points for mild improvement. Analysis revealed that the subjects felt that placebo (3.8 average) helped more than the ginseng (3.2 average). The authors concluded that ES supplementation did not have an ergogenic effect on submaximal or maximal exercise tasks.4
5. In another eight-week experiment, 19 men and women consumed either 400 mg of a standardized Panax ginseng extract a day or a placebo. There was no difference between peak anaerobic power, mean anaerobic power or rate of fatigue during an all-out exercise bicycle ride to exhaustion. The authors concluded that chronic ginseng supplementation did not have an ergogenic effect on short duration, supramaximal exercise.5
6. The final study used a randomized, double-blind, crossover design and included 10 highly trained male cyclists who were given either 1200 mg a day of ES or a placebo for seven days prior to each of two trials. The trials were 120 minutes of steady state cycling followed by a 10 km timed trial. Many factors, including oxygen consumption, HR, plasma lactate and rate of perceived exertion were measured every 20-30 minutes during the two hour ride and again following the 10 km timed trial. There were no differences between ES and placebo for any of the factors measured. The authors concluded that ES supplementation did not demonstrate an ergogenic effect in either steady state or timed trial activities.6
In his book, Optimum Sports Nutrition, Michael Colgan states that for ginseng to be effective, 200 mg of standardized extract, or approximately 10 gm of nonstandardized pure ginseng need to be used daily over a period of months to have an effect. Dr. Colgan disagrees with eastern Europeans on the value of eleutherococcus senticosus and does not recommend it.7 Therefore, of the six negativestudies quoted, only the fifth meets Dr. Colgan's criteria.
Conclusion
Based on these papers, it appears that standardized ginseng extract, Panax ginseng and eleutherococcus senticosus neither help nor harm athletic performance with short-term use. Whether long-term use of products rich in ginsenosides will be of benefit is still debatable. Without some well-designed positive studies in the near future, ginseng use among athletes will probably begin to decline.
The results of these studies should not be extrapolated to conclude that various forms of ginseng cannot affect human health in other ways. All of the people in these studies were young (ages 20-45) and in good physical condition. We do not know if ginseng would have a selected benefit for unfit individuals.
Finally, researchers at the Rochester Institute of Technology tested various commercial ginseng preparations for another family of compounds called methylxanthines (the most well known methylxanthine is caffeine). They found a wide range of xanthines (1 mg to 200 mg per dose) in various commercial ginseng preparations.8 This may partially explain why some people (caffeine-sensitive) feel that ginseng helps their endurance. There is extensive literature that shows that caffeine can help endurance, in fact, if blood levels of caffeine are too high, Olympic athletes can be disqualified.9
References
- Morris AC, Jacobs I, et al. No ergogenic effect of ginseng ingestion. International Journal of Sport Nutrition 1996;6:263-271.
- Allen JD, McClung J, Welsch M. The effects of short-term ginseng supplementation on maximal exercise performance in healthy young adults. Medicine and Science in Sports and Exercise May 1997;29(5S):A1438.
- Lifton B, et al. The effect of ginseng on acute maximal aerobic exercise. Medicine and Science in Sports and Exercise May 1997;29(5S):A1414.
- Dowling E, Redondo D, et al. Effect of eleutherococcus senticosus on submaximal and maximal exercise performance. Medicine and Science in Sports and Exercise April 1996;28(4):482-489.
- Kolokouri I, et al. Effect of chronic ginseng supplementation on short duration supramaximal exercise test performance. Medicine and Science in Sports and Exercise May 1999;31(5S):S117.
- Eschbach LC, et al. Effect of eleutherococcus senticosus (Siberian ginseng) on substrate utilization and performance during prolonged cycling. Medicine and Science in Sports and Exercise May 1999;31(5S):S117.
- Colgan M. Optimum Sports Nutrition. New York: Advanced Research Press, 1993, pp. 305-310.
- Vaughn MA, Doolittle RL, et al. Physiological effects of ginseng may be due to methylxanthines. Medicine and Science in Sports and Exercise May 1999;31(5):S121.
- Bucci L. Nutrients as Ergogenic Aids for Sports and Exercise. Boca Raton, FL: CRC Press, 1993.
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