Ergogenic Aids – Should I or Shouldn’t I? (Part 1 of 2)
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| Reyna F |
There are many products on the market and new ones are continually emerging. Here are just a few products that athletes may think about using and information that will help you answer the risk/benefit questions.
Amino Acids (AA): Arginine, Lysine, Ornithine
Claims about Amino Acids:
It is claimed that amino acid supplementation increases human growth hormone secretion. This secretion is believed to also affect the anabolic processes. As a result, muscle mass increases and body fat is reduced.
Research on Amino Acids:
Studies have shown that amino acid supplementation does not actually enhance performance. Although daily dietary protein requirements are higher for athletes, most athletes get enough protein to meet this increase without supplementing with amino acids, the building blocks of protein. Clinical studies have also shown that endurance does not improve with amino acid supplementation.
For instance, Corpas et al. examined if oral arginine and lysine supplements could effect hGH in older men. 16 men were divided into two groups, and received 3 grams of arginine and lysine twice daily for two weeks. Level of hGH were measured through blood samples. Both hGH or serum insulin growth factor were not altered significantly, thus oral AA supplementation did no prove to be effective.
In another research project, Suminski et al. studied AA ingestion and resistance training, and the effects it has on plasma growth hormone concentration levels in young men. 16 males partook in four separate trials. Each subject was randomly assigned either to amino acid and exercise, exercise and placebo, amino acid alone, or placebo alone. Those supplementing took 1500 mg of arginine and lysine just before exercising. Concentrations of hGH were elevated during exercise but there were no noted differences in performance between the two exercise groups.
Amino Acid supplements are currently legal and not prohibited by any sports governing agencies. However, research has not found them to be effective. If you do choose to supplement with amino acids, be careful. Large intakes of some single amino acids may interfere with absorption, lead to metabolic imbalances and cause stomach distress. At this time, it is best to avoid large intake of single amino acids until its safety is determined.
Beta-Hydroxy-Beta-Methylbutyrate (HMB)
Claims about HMB:
HMB supplementation is used to decrease protein breakdown and increase synthesis. HMB is said to increase muscle mass, decrease body fat, and enhance power and strength.
Research on HMB:
Research has not found HMB to enhance performance in trained athletes. For instance, Slater et al. conducted a six-week study, which revealed that supplementation did not increase strength when combined with resistance training.
O’Conner and Crowe also examined HMB supplementation. They conducted a randomized trial with 27 elite rugby players. HMB did not affect aerobic performance during multistage fitness test or on anaerobic performance during a 60 second maximal cycle test.
With this in mind, only two studies show support that HMB reduces muscle proteolysis and increases strength and muscle size. These studies were published together by Nissen et al. The results for the first study, which examined 41 untrained male participants, were not statistically significant, but did reveal that those subjects supplementing with HMB gained more lean body mass in a dose-responsive manner. HMB groups were also able to perform significantly more abdominal exercises than the placebo group was able to do. The second study, which looked at 32 male, trained participants, found that HMB supplementation increased bench press strength by almost threefold; this was a significant increase. However, fat free mass was not significantly different between the HMB and placebo group. It should be noted that these two studies were conducted in the same lab group that developed HMB.
HMB is a legal supplement; the International Olympic Counsel (IOC) and The National Collegiate Athletic Association (NCAA) do not prohibit the use of supplementing with HMB. Not found to be effective.
While Nissen et al., did find HMB to be effective, it should be considered that other experiments have not seen the same results. Additionally, no immediate adverse effects have been seen, however, evidence is lacking for long term consequences. With all of this in mind, it is best not to supplement with HMB.
Branched Chain Amino Acids (BCAA)
Claims about BCAAs:
Branched Chain Amino Acids are said to prevent fatigue and increase aerobic endurance by competing with tryptophan (f-TRP). TRP is released during exercise and contributes to fatigue. BCAA levels decrease during endurance exercise because our muscles oxidize them for energy. Thus people supplement with BCAA to prevent fatigue and increase their aerobic endurance capacity.
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| Exaggerated/Inaccurate Claims? |
Research has been conducted concerning BCAA supplementation and its effectiveness. In one study, Klavs et al. examined the performance enhancing effects of glucose, glucose plus BCAA or a placebo on 9 trained cyclists. The cyclists performed in a 100-km time trial. Results found no difference in performance times between the three groups.
Davis et al., examined the effect of a 6% carbohydrate-electrolyte drink, a 12% carbohydrate-electrolyte drink and water placebo on prolonged cycling in fatigue at 70% of VO2 max. Subjects who drank the placebo saw a seven-fold increase in plasma f-TRP. For those subjects who drank 6 or 12 percent carbohydrate –electrolyte drink, the increase in plasma f-TRP was reduced greatly. Fatigue was delayed by about one hour in these subjects.
Recommendations:
While there is a logical theoretical basis that supports BCAA supplementation for endurance athletes, the data is limited and ambiguous.
One concern with BCAA supplementation is the fact that a large amount is needed to impact performance. This may increase plasma ammonia levels. High ammonia levels in the body could be toxic to the brain and impair muscle metabolism. Water absorption could also be slowed down from the gut and cause GI disturbances.
With this in mind, along with the fact that BCAAs are abundant in food, it is not recommended to supplement with BCAAs.
Caffeine
Claims about Caffeine:
This stimulant is said increase energy and decrease fatigue, as well as increases fat loss and endurance.
Research about Caffeine:
Research on caffeine as an ergogenic aid began in the late 1970s. Costill et al. conducted a study with nine competitive cyclists as participants. These cyclists consumed 330 mg of caffeine an hour before a cycling bout. The cyclists were able to ride 19% longer before reaching exhaustion. Costill et al. performed another study which found that consuming 250 mg of caffeine increased the amount of work performed in two hours by 20%. Both these studies also suggested that caffeine increased the utilization of fat for energy by 30%.
Research concerning caffeine supplementation continued. In 1980, a study created by Essig et al. discovered that supplementing with 5 mg of caffeine/kg during a 30 minute cycling bout decreased usage of muscle glycogen by 42% and was able to increase the use of muscle triglyceride by 150% . Following these studies research on caffeine’s effect on exercise performance was limited and inconsistent. For instance, in 1991 Graham and Spriet examined the effects caffeine has on competitive distance runners. Participants ingested 9 mg caffeine/kg an hour before running and cycling until the point of exhaustion. Those supplementing with caffeine saw an average increase of 51% for the cycling bout and 44% for the running test. However, caffeine levels in the urine in 4 of the 12 trials were close to or above the IOC threshold of 12 mcg mL.
Graham and Spriet conducted another study which analyzed various doses of caffeine on 8 well-trained participants. Participants avoided caffeine for 2 days and then consumed either 3, 6 or 9 mg of caffeine/kg or a placebo an hour before exercise. Those participants that consumed 3 and 6 mg/kg of caffeine saw an increase in endurance, while those consuming 9 mg did not. Plasma epinephrine levels increased in participants who consumed 6 or 9 mg/kg of caffeine. Those who consumed 9 mg/kg also saw elevated free fatty acids and glycerol levels. From this research, it was established that a low dose of caffeine, 3 mg/kghas an ergogenic effect without increasing epinephrine levels.
Further research supports caffeine as an ergogenic aid. Kovacs et al. examined caffeine as an ergogenic aid. Found that participants cycled faster when supplementing with caffeine. Finally, Bruce et al. examined the effect of caffeine ingestion on a 20000-meter rowing session. Discovering that those who supplemented with caffeine reduced their times by 1.2 percent.
Recommendations:
Caffeine is a legal substance. However, the IOC currently prohibits urinary concentrations greater than 12 mcg/mL. The NCAA also has created restrictions. Allowing up to 15 mcg/mL of caffeine urinary concentration. Supplementing with caffeine is generally seen as safe, however, side-effects can occur if caffeine is consumed in a high amount. This consequences are: muscle tremors, anxiety, dependency, headache, nausea, and palpitations. Those who are sensitive to caffeine may even experience these effects at low dosages.
Research has been able to suggest a safe amount of caffeine. Through their research Graham and Spriet deduced that consuming 3-13 mg of caffeine/kg can enhance performance by 20-50% in athletes. They also suggest that dosages of 3-6 mg/kg one hour before exercise may create an ergogenic effect and not increase urinary caffeine levels above the IOC doping threshold. Higher doses of 9-13 mg/kg may also enhance performance, but with consequences. They are also likely to raise urinary caffeine levels above the IOC and NCAA thresholds.
Creatine
Claims about Creatine:
Research:
Research conducted on creatine has revealed mixed results. For instance, Dempsey et al., conducted a meta-analysis of 16 controlled trials. In these trials they found that supplementing with creatine increased the maximal weight lifted by the young men that participated in the study. Women and persons older than 60 years old were not impacted by creatine supplementation.
Further more, a branch conducted a meta-analysis of 100 studies of varying designs found that creatine enhanced performance of repetitive bouts of exercise that lasted less than 30 seconds each. Supplementation did not show to enhance swimming or running performance.
Greenhaff researched the adequate dosage of creatine needed to be effective. He examined what happens to those who ingested a total of 20-25 g/day of creatine monohydrate (405 doses of 5g / day) for 5- 7 days. Discovering this method can create up to a 20% increase in muscle creatine levels. He also notes that after this loading period, a maintenance dose is needed of 2-5 g/day to maintain these elevated levels.
Volek et al. researched the effect creatine supplementation has on muscular performance during repeated bouts of high-intensity resistance exercise. The study concluded that resistance-training athletes may enhance performance through supplementing with creatine since the substance allows athletes to train harder.
Various research conducted has found creatine to be effective as an ergogenic aid. It has been shown to increase strength during resistance training in both football players and sedentary females. It has also been shown to increase maximal power output during sprints, enhance both single and repeated sprint performance, and increase the amount of time cyclists can cycle before reaching the point of exhaustion.
However, studies have also found adverse effects from creatine. Short-term supplementation of creatine (three-five days) has been showed to increase weight due to increase in total body water. Long-term side-effects also exist. A study conducted by Groeneveld et al. examined the long term effects of creatine supplementation. Creatine supplementation for 310 days was studied examining 175 participants. These participants showed an increase in limb edema at the 2nd month, but none after this mark. Participants did not show an increase in GI discomfort, nausea, diarrhea or renal dysfunction
Some studies have shown that creatine has no or limited effect on both sprint and strength performance. Studies have also revealed that creatine is not effective for endurance exercise. Engelhardt et al., studied the effect creatine has on triathletes. These participants received 20 g of creatine or a placebo for 5 days and were tested on their endurance performance. Results indicated that creatine supplementation significantly increased power performance by 18%. No impact was seen on endurance.
In young, healthy people creatine supplementation seems to have minimal effect on serum creatine concentration. Further studies are needed for older people and those with renal dysfunction. Supplementing with creatine also increases fat-free mass (FFM). Whether it is due to fluid retention or increase in protein synthesis has yet to be determined. Kredier et al., studied total body weight compared to body water over 28 days of supplementation in football players versus a control group. Results showed that creatine supplementation increased total body mass by 2.42 kg with no significant increase in total body water.
Creatine is legal and can be effective. However, its effectiveness is in limited contexts. As a result, it is not recommended for everyone. Because it is only good for short bursts of energy, such as weight training and sprints, creatine is not recommended for endurance athletes.
Many reports have shown that supplementing with creatine has increased incidences of muscle pulls, muscle cramps, tendon pulls, and muscular injuries. However, studies evaluating highly trained athletes during heavy training periods have not reported these side effects.
There is also concern about the supplementation adding stress to liver and kidney function. Yet this has not been reported in healthy individuals.
However, keep in mind the long-term safety of creatine has not been established.
Dosage recommendations have been established. First athletes should begin a loading phase of 20-25 g / day for 7-5 days. Taking 5 g 4-5 times per day. After this a maintenance phase of 5 g /day should be implemented. A washout period should also be implemented of about 4 weeks. Creatine should not be taken for extended periods of times.
-Reyna F
MS, RD, CSSD, CPT
Nutrition and Exercise Consulting
www.reynafranco.com/
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