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Chen et al. Journal of Physiological Anthropology 2012, 31:4http://www.jphysiolanthropol.com/content/31/1/4 Herbs in exercise and sports Chee Keong Chen*, Ayu Suzailiana Muhamad and Foong Kiew Ooi The use of herbs as ergogenic aids in exercise and sport is not novel. Ginseng, caffeine, ma huang (also called‘Chinese ephedra'), ephedrine and a combination of both caffeine and ephedrine are the most popular herbs usedin exercise and sports. It is believed that these herbs have an ergogenic effect and thus help to improve physicalperformance. Numerous studies have been conducted to investigate the effects of these herbs on exerciseperformance. Recently, researchers have also investigated the effects of Eurycoma longifolia Jack on endurancecycling and running performance. These investigators have reported no significant improvement in either cyclingor running endurance after supplementation with this herb. As the number of studies in this area is still small,more studies should be conducted to evaluate and substantiate the effects of this herb on sports and exerciseperformance. For instance, future research on any herbs should take the following factors into consideration:dosage, supplementation period and a larger sample size.
Keywords: herbs, ginseng, caffeine, ephedrine, Eurycoma longifolia Jack tinctures, as well as standardized root extracts contain- According to botanists, ‘herb' is defined as a soft- ing known amounts of ginsenosides in every batch [ stemmed plant which dies after flowering, whereas herb- Ginseng roots contain approximately 13 glycosylated alists define an ‘herb' as any part of a plant which can steroidal saponins (ginsenosides) which are the probable be used for medicine, cooking, cosmetics and as a scent active agents Ginseng is thought to be a tonic or dye. In nature, there are many types of herbs that that can improve vitality, health and longevity. Separa- can be found and have been used traditionally for many tion of ginsenosides and administration to animals has purposes. Athletes are among those who use herbs for revealed activities which stimulate the central nervous their own benefit. They believe that some herbs may system Other probable functions of ginseng help them to improve their performance, speed up include increased production of corticotropin and corti- recovery, maintain health and fitness during intense per- sol in animals and humans and anabolic actions in ani- iods of training, increase muscle mass and reduce body mals In addition, ginseng has been shown to fat. Ginseng, caffeine, ephedrine and recently Eurycoma possess antioxidant properties whereby it scavenges longifolia Jack are among the popular herbs used to hydroxyl radical and inhibits lipid peroxidation [].
enhance exercise and sports performance. In this article, Ginseng has also been touted as possessing a stimulant we review some of the studies of these herbs to investi- effect and thus improves alertness and decreases fatigue gate their effects on exercise and sports performance.
and stress . Consequently, various possible mechan- 'Ginseng' is a general name for the plant genus Panax.
isms of ginseng ingestion have been postulated to con- Some of the members of genus are Panax ginseng, tribute to the enhancement Panax quinquefolius, Panax notoginseng and Panax japonicus. Among these plants, Panax ginseng, also In a number of animal studies, ginseng has been known as Chinese or Korean ginseng, is the one which reported to improve exercise performance. Researchers is most widely used Ginseng is available in various in some other animal studies, however, have reported forms, such as whole root, root powder, teas and that the use of large doses or parenteral administrationcould weaken extrapolation of these scientific data tohumans [. In exercise and sports science, ginseng * Correspondence: is believed to be a physical performance enhancer Sports Science Unit, School of Medical Sciences, Universiti Sains Malaysia,16150 Kubang Kerian, Kelantan, Malaysia However, a review of the available data on the effects of 2012 Chen et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative CommonsAttribution License ), which permits unrestricted use, distribution, and reproduction inany medium, provided the original work is properly cited.
Chen et al. Journal of Physiological Anthropology 2012, 31:4 ginseng on human exercise performance reveals dose- Researchers in related studies have revealed that caf- response and duration effects, which may account for feine supplementation can improve performance at vary- the equivocal results reported [Its chronic use has ing intensities and modalities of exercise and been believed to improve cardiorespiratory function and evidence of its effects on submaximal exercise has also lower lactate concentration in the blood in addition to been well-documented However, its effect on inter- improving physical performance Nevertheless, it mittent sprint performance is still lacking [It has has been reported that its benefits were best seen in been reported that plasma concentration of caffeine is individuals in poor physical condition maximal 1 hour after ingestion and returns to normal 6 Many study investigators have found that ginseng can hours after ingestion [. Thus, for ergogenic purposes, increase exercise duration until exhaustion during a dose of caffeine ranging from 2 to 9 mg/kg body mass forced exercise trials ]. This was believed to be due has been suggested to be effective, and the caffeine to stress adaptation via ginseng supplementation [.
should be taken at least 1 hour prior to exercise or Panax ginseng has been investigated extensively for its stress-attenuating activity It is a well-known adap- The effect of caffeine on endurance was reported in a togen and has been shown to be effective in attenuating study where there was a significant increase (44%) in stress-induced adverse effects in astronauts and soldiers endurance running performance after athletes ingested 9 ]. Rai and colleagues [demonstrated that Panax mg/kg body mass of caffeine 1 hour prior to exercise ginseng has potent adaptogenic activity that is mediated Caffeine is a well-documented stimulant of the by regulation of pituitary adrenocorticotropic hormone central nervous system as well as the cardiovascular and secretion to combat stress. This adaptation to stress respiratory systems. It is believed that caffeine ingestion may increase exercise time to exhaustion . For exam- increases blood catecholamine concentration ,].
ple, Liang et al. reported that, in untrained adults, Furthermore, its ergogenic effect on sports performance consumption of one 1, 350-mg Panax notoginseng cap- is also attributed to its effect on substrate availability, sule per day for 30 days improved their endurance time namely, free fatty acids Increases in free fatty acid by more than 7 minutes and lowered their maximal concentration in turn lead to a glycogen-sparing effect mean blood pressure and maximal oxygen consumption because the body's energy system will start using (VO2max) at the 24th minute during endurance cycling free fatty acid as a primary source of fuel. A recent exercise. McNaughton et al. conducted a placebo- study demonstrating endurance enhancement with caf- controlled cross-over study in which the subjects were feine supplementation (5 mg/kg body weight) showed a given Chinese ginseng, Siberian ginseng or placebo sup- significantly higher level of plasma free fatty acids in the plements (1 g/day for 6 weeks for each supplement).
caffeine trial compared to the placebo trial Glyco- They reported that Chinese ginseng significantly gen sparing can delay the onset of exhaustion; conse- increased maximal oxygen consumption, postexercise quently, physical performance can be enhanced recovery and pectoral and quadriceps strength, but Researchers in two studies who used the needle biopsy handgrip strength did not change after the supplementa- procedure demonstrated a glycogen-sparing effect fol- tion regimen. Furthermore, it has been shown that a lowing caffeine supplementation In addition, single dose of Panax ginseng (200 mg) can modulate cir- Kamat et al. proposed that the ergogenic effect of culating blood glucose level, enhance cognitive perfor- caffeine could be due to its antioxidant property. How- mance on a mental arithmetic task and ameliorate the ever, more studies need to be conducted to substantiate increase in subjective feeling of mental fatigue during sustained intense cognitive processing Collomp et al. investigated the beneficial effects It has been reported that the use of ginseng does not of caffeine ingestion on sprint performance in trained lead to any positive test results for banned substances and untrained swimmers. Subjects' swimming velocity after urine testing of elite athletes, although ginsenosides and blood lactate concentrations were observed to and their metabolites were detectable in the sera and determine the plausible effects of caffeine. The subjects urine of athletes following the ingestion of ginseng were required to perform 100-metre freestyle swimming ]. Panax ginseng has certain ergogenic properties twice at maximal speed: once after ingestion of 250 mg that may improve both physical and mental performance, of caffeine and the other after placebo ingestion. These provided that the dosage is adequate (≥ 200 mg/day) and two tests were separated by 20 minutes of passive recov- the supplementation period is of sufficient duration (≥ 8 ery. The study results showed that the swimming velo- weeks). In addition, supplementation of Panax ginseng city of the trained swimmers was significantly improved has been proven to be safe on the basis of animal toxicity after caffeine ingestion and that maximal blood lactate studies which demonstrated that ginseng does not result concentration was significantly enhanced in both in teratogenicity or mutagenicity untrained and trained subjects after caffeine ingestion.
Chen et al. Journal of Physiological Anthropology 2012, 31:4 Caffeine is also associated with mental alertness and It is postulated that the positive effects of ephedrine mood. Yeomans and colleagues [found that inges- can be seen when it is combined with caffeine on the tion of 1 and 2 mg/kg caffeine at breakfast decreased basis of studies in which caffeine was believed to reaction time and improved rated mental alertness, thus potentiate the effects of ephedrine [. For instance, increasing performance. They also found that a 1 mg/kg the combination of caffeine and ephedrine has been dose of caffeine could increase performance accuracy.
found to increase the time to exhaustion during a stan- Similarly, ingestion of 1 mg/kg caffeine 60 minutes after dard high-intensity cycle ergometer exercise test breakfast in the subjects who did not consume any caf- Another study showed that after ingesting 75 mg of feine during breakfast also improved their rated mental ephedrine and 375 mg of caffeine, there was a signifi- alertness and decreased their reaction time. However, cant decrease in the completion of a 3.2-km run In doubling caffeine ingestion did not improve those another study, 10 km of running on a treadmill was 1 effects; the effects of caffeine in the subjects who minute faster after the ingestion of ephedrine or a com- ingested caffeine during breakfast and 60 minutes after bination of ephedrine and caffeine when compared to breakfast were similar to those who ingested caffeine the placebo trial ]. These data raise speculation that once, either only during breakfast or 60 minutes after the effect of the combination of caffeine and ephedrine breakfast. This study demonstrated that the effects of occurs as a result of central nervous system stimulation.
caffeine occur only in the caffeine-deprived subjects.
Furthermore, it has been reported that ingestion of this Chinese ephedra, or ‘ma huang', is a sporophyte herb combination decreased the rate of perceived exertion that has also been studied for its effects on exercise per- during high-intensity exhaustive exercise . Individual formance It is found mainly in Pakistan, China ephedrine alkaloids do not seem to augment physical and northwestern India. The active ingredients consist performance, but, when combined with caffeine, they of ephedrine and related alkaloids It is a sympatho- apparently have a synergistic effect that prolongs exer- mimetic alkaloid because it mimics epinephrine effects cise time to exhaustion.
and stimulates the sympathetic nervous system Eurycoma longifolia Jack is one of the herbs found in Receptors for ephedrine in human body are found on Malaysia. It is commonly known as ‘tongkat ali' in most cells, including the heart, lungs and blood vessels.
Malaysia and as ‘pasak bumi' in Indonesia. It is also Ephedrine was claimed to have ergogenic properties referred to as ‘Malaysian ginseng' because it is well- whereby it was believed to improve aerobic performance known among various ethnic groups in Malaysia as a and endurance by reducing fatigue, increasing alertness, treatment for various diseases and enhancing health improving reaction time and increasing strength Eurycoma longifolia Jack is a tall, single-stemmed, However, a number of studies in which investigators slender, shrubby, slowly growing tree, and it can be examined the effects of ephedrine or pseudoephedrine found on sandy soil. It belongs to the Simaroubaceae on exercise performance in humans have demonstrated family and grows wildly in Southeast Asian countries, that there was no enhancement of performance when that is, Malaysia, Indonesia, Thailand, Myanmar, Laos the normal dosages (≥ 120 mg/day) considered safe were ingested Sidney and Lefcoe ] gave 24- This herb has been used as an anticoagulant for com- mg ephedrine supplements to 21 males and reported no plications during childbirth, a treatment for dysentery significant differences compared with placebo in muscle an aphrodisiac an antimalarial agent strength, endurance or power, speed, lung function, an antibacterial ointment an anticancer hand-eye coordination, reaction time, anaerobic capacity medicine ], an antihyperglycaemic therapy and and cardiorespiratory endurance, maximal oxygen con- an anxiolytic The pharmacological activity of this sumption and ratings of perceived exertion. Swain et al.
plant is actually attributed to these various quassinoids administered 1 and 2 mg/kg pseudoephedrine or and also to the squalene derivatives biphenylneolignans, 0.33 and 0.66 mg/kg phenylpropanolamine or placebo to tirucallane-type triterpenes, canthine-6-1 and b-carbo- ten trained cyclists who were then required to undergo line alkaloids [Mohd Tambi ] reported that con- testing on a bicycle ergometer and a urine drug test.
sumption of water-soluble extract of Eurycoma There were no significant differences in maximal oxygen longifolia Jack, even at a high dose of 600 mg, is non- consumption, ratings of perceived exertion, blood pres- toxic in humans.
sure, peak pulse rate or time to exhaustion between Published scientific data regarding the effects of Eury- trials. Similarly, Gillies et al. reported no significant coma longifolia Jack on exercise performance are scarce.
changes in a cycling time trial performance or muscle Nevertheless, the acute effects of an herbal drink con- function when ten subjects were given either 120 mg of taining Eurycoma longifolia Jack on cycling endurance pseudoephedrine or placebo in a randomized, double- performance were investigated [In this previous blind, placebo-controlled cross-over study.
study, subjects were given a low dosage of Eurycoma Chen et al. Journal of Physiological Anthropology 2012, 31:4 longifolia Jack (approximately 0.67 mg of Eurycoma supplementation (150 mg for 5 weeks) can increase longifolia Jack per trial) during endurance cycling per- muscle strength Therefore, we believe that the sup- formance. The young, trained male cyclists ingested plementation period and maybe the dosage used in our either an herbal drink or placebo and cycled as long as previous study were still insufficient to elicit the benefi- possible at 70% VO2max for the first hour and at 80% cial effects of Eurycoma longifolia Jack on endurance VO2max thereafter until exhaustion during the experi- performance and physiological responses. Thus further mental trials. It was reported that there was no signifi- study at higher dosages and for longer supplementation cant improvement in cycling performance or in the periods may be warranted to determine its effects on physiological responses between the two trials in this exercise and sports performance.
study. It is speculated that the results could be due to Some of these herbs have been shown to have benefi- the inadequate concentration of Eurycoma longifolia cial effects on psychological states. For example, ginseng Jack in the drink (0.1 mg/100 ml of drink) which was has positive effects on stress, caffeine improves mental given to the subjects during the cycling trials.
alertness and mood and Eurycoma longifolia Jack has Subsequently, we conducted another study to investi- anxiolytic (that is, antianxiety) properties. However, how gate the effects of Eurycoma longifolia Jack on endur- these changes in psychological states as a result of her- ance running performance with a higher dosage of this bal supplementation affect sports performance has not herb and a longer supplementation duration [ been well-studied. Hence further studies could also Twelve recreational athletes were recruited to partici- focus on the effects of these herbs on psychological pate in this study, in which they were asked to consume states and determine if these effects (if any) are asso- two capsules of the supplement (75 mg of Eurycoma ciated with a concomitant improvement in sports longifolia Jack per capsule) or placebo capsules daily for 7 days before and again 1 hour prior to the exercisetrial. We observed that this amount of Eurycoma longi- folia Jack (150 mg daily for 7 days) had no beneficial Table summarises the selected studies on the effects effects on the participants' endurance running perfor- of ginseng, caffeine, ephedrine, a combination of caffeine mance and physiological responses. However, it has and ephedrine, and Eurycoma longifolia Jack in exercise Eurycoma longifolia Jack and sports performance. It can be observed from the Table 1 Selected studies on the effects of ginseng, caffeine, ephedrine, combination of caffeine and ephedrine, andEurycoma longifolia Jack in exercise and sports 2 g of Panax ginseng extract or Exhaustive incremental exercise on Increased exercise duration until placebo three times per day for 8 exhaustion and facilitation of recovery from exhaustive exercise For 30 days: 1, 350 mg/day Panax Endurance exercise on cycle Improved endurance exercise time ginseng or placebo ergometer at 65% to 70% VO2 peak. to exhaustion with Panax ginseng Exercise intensity increased by 30 W at every 5-minute interval after first35 minutes of exercise untilexhaustion.
Ping et al., 2010 1 hour prior to exercise: 5 mg/kg Running to exhaustion at 70% Improved endurance running body weight of caffeine or placebo VO2max on a motorised treadmill in performance in the heat the heat (31°C and 70% relativehumidity) 1 hour before exercise: 5 or 2.5 mg/ Exercise rides to exhaustion on cycle Increased exercise time to kg body mass of caffeine or placebo ergometer at 80% VO2max performed in the morning and 5hours later on the same day 0, 5 or 9 mg/kg body mass of Maximal effort of 21-km road racers Race performance in high heat outdoors in hot and humid stress not affected by caffeine competitiveroad racers(ages 23 to 51years old) Chen et al. Journal of Physiological Anthropology 2012, 31:4 Table 1 Selected studies on the effects of ginseng, caffeine, ephedrine, combination of caffeine and ephedrine, andEurycoma longifolia Jack in exercise and sports (Continued) Single dose of 250 mg of caffeine or 2 × 100-metre freestyle swims at Trained subjects exhibited significant maximal speed separated by 20 improvement in swimming velocity minutes of passive recovery after caffeine supplementation Ingestion of coffee containing 339 Exercise until exhaustion on a Cycling time with caffeine ingestion mg of caffeine or exercise without bicycle ergometer at 80% VO2max greater than non-caffeine fluid 1 hour before exercise: 9 mg/kg Four exercise trials at approximately Endurance time increased with Spriet, 1991 competitive body mass of caffeine or placebo 85% VO2max: two trials of running caffeine supplementation in both to exhaustion and two trials of cycling to exhaustion.
Schneiker et al., 6 mg/kg body mass of caffeine or Two 36-minute halves, with each Total amount of sprint work placebo 1 hour before exercise half composed of 18 × 4-second performed and mean peak power sprints and 2 minutes of active score achieved during sprints were recovery at 35% VO2 peak between greater with caffeine ingestion in both exercise halves A single dose of ephedrine (24 mg) Muscle strength, endurance and No effect on any of the males (ages 19 or placebo measurements of physical work Caffeine +ephedrine 2 hours before trials: combination of Trials of the Canadian Forces Warrior Run time significantly faster in the 375 mg of caffeine and 75 mg of Test (3.2-km run wearing ‘fighting treatment group compared with ephedrine or placebo order' which weighed about 11 kg).
placebo, and test performance wasimproved by caffeine and ephedrine Bell et al., 2000 1.5 to 2 hours before exercise: 5 Cycling to exhaustion on a cycle Time to exhaustion in the treatment mg/kg body mass of caffeine plus ergometer at 85% VO2 peak trial greater than placebo 0.8 mg/kg body mass of ephedrine,4 mg/kg body mass of caffeine plus1 mg/kg body mass of ephedrine, 4mg/kg body mass of caffeine plus0.8 mg/kg body mass of ephedrine,or placebo Bell et al., 1998 1.5 hours before exercise: 5 mg/kg Exercise on a cycle ergometer at a Only the combination of caffeine body mass of caffeine, 1 mg/kg maximal power output until and ephedrine led to a significantly body mass of ephedrine, longer time to exhaustion than combination of both caffeine and ephedrine, or placebo Bell et al., 2002 4 mg/kg body mass of caffeine, 0.8 10-km run in a climatic suite at 12°C Running time decreased in mg/kg body mass of ephedrine, to 13°C on treadmill while wearing a ephedrine and combination of combination of both caffeine and helmet and backpack weighing 11 ephedrine and caffeine trials.
ephedrine, or placebo kg. Speed was regulated by subjects. Running pace increased in ephedrine compared withnonephedrine groups over the last5 km of the run.
45 minutes before exercise: 300 mg Maximal strength exercise of bench Increased alertness and enhanced of caffeine, 300 mg of caffeine plus press (BP) at one repetition mood after supplementation of 60 mg of ephedrine, or 300 mg of maximum (1 RM) and latissimus combination of caffeine and dorsi pull-down (LP) at 1 RM. Each ephedrine. No differences in muscle subject also performed repeated strength, endurance or peak aerobic repetitions at 80% of 1 RM on both BP and LP until exhaustion.
Eurycomalongifolia Jack Muhamad et al., 12 recreational Two capsules per day containing 75 60-minute run on treadmill at 60% Running distance during time trial mg of Eurycoma longifolia Jack or VO2max followed by 20-minute time with Eurycoma longifolia Jack was (age 23.3 ± 3.7 placebo for 7 days before and not different from placebo.
another two capsules 1 hour before Physiological responses were also not different between trials.
Ingestion of herbal drink containing Cycling at 70% VO2max for the first No significant improvement in 0.1 mg of Eurycoma longifolia Jack hour and 80% VO2max thereafter cycling performance or physiological per 100 ml of drink (about 0.67 mg of Eurycoma per trial) or placebodrink during exercise VO2max, maximal oxygen consumption; VO2 peak, peak oxygen consumption.
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Authors' contributions Cui JF, Garle M, Björkhem I, Eneroth P: All authors participated in the design of the study of Eurycoma longifolia Jack. AS and FK searched for more articles and journals related to the effects of supplements on exercise and sports performance. All authors read and Invest 1996, 56:151-160.
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were recommended by the reviewers. All authors read and approved the Schneiker KT, Bishop D, Dawson B, Hackett LP: final manuscript.
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