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“Do I need supplements?” It’s a question I’m often asked by clients at the
Boulder Center for Sports Medicine. The answer? It depends—and I’m not trying
to weasel out of a direct response. It’s hard to be more specific for two
reasons. First is the dizzying array of supplements available: supplements for
performance, for remedying dietary deficiencies and simply for insurance in case
your diet is marginally inadequate in one or more nutrients. And, of course, it
depends on the type of activity you’re engaged in and the level of performance
you’re trying to achieve. So I apologize for saying it depends—but, hey, it’s
a complicated question!
So I’ll stop weaseling now—and give a ball park answer. I divide supplements
into four categories:
- those that are definitely worth it
- others that are possibly useful
- supplements that are a proven waste of time and money
- and those that are potentially harmful.
Hundreds of supplements crowd the shelves of health food stores, all of them
claiming to make you healthier, faster and stronger. It’s impossible to review
them all. Here’s a sampling of the most popular supplements in each category.
Definitely Worth It
- Caffeine. A number of studies have shown that caffeine improves endurance
performance. Opinion is currently divided about how this takes place but caffeine
stimulates the central nervous system, increasing psychological arousal, an
advantage in many sports. The recommended dose is 5 mg per kilogram of body
weight so a 70 kilogram (154 pound) athlete would consume 350 mg (about the
amount in three to four cups of brewed coffee.) Caffeine is classified as a
stimulant by the International Olympic Committee (IOC) but its use is allowed in
moderation. A level above 12 micrograms per milliliter of urine is grounds (sorry
for the pun) for disqualification. Drawbacks: some people get jittery and
nervous when they use caffeine and it’s also a mild diuretic, possibly leading to
frequent pit stops during competition.
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Resources |
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For more information, a great reference is The Ergogenics Edge
by Mel Williams.
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Creatine. Creatine is a natural component of diet, found in animal foods. It’s
also synthesized in the liver from certain amino acids. Recent research indicates
that creatine improves short duration, power sports performance. For instance,
some studies show that, in repeated sprints, creatine improves the ability to
sustain speed in the last few repetitions. Recommended doses formerly included
a “loading” period of about five days with doses of 5 grams a day but a steady
dose of 2 grams/day seems to work as well. Creatine supplementation doesn’t
appear to involve health risks but its long-term safety hasn’t been studied.
Drawbacks include weight gain from water retention, which could be a liability
for endurance sports performance. Some athletes report increased incidence of
cramping and muscle pulls.
- Sports Drinks. Probably the most effective supplement is as close as your water
bottle—carbohydrate taken during endurance exercise in the form of sports drinks.
Numerous studies over the last 50 years have shown that a drink containing 6–9%
carbohydrate, taken at the rate of 4 to 6 ounces every 15 minutes during exercise,
significantly improves performance and endurance. Simple, safe and effective.
Possibly Useful
- Antioxidants. Some research indicates that supplementing the diet with antioxidants
(betacarotine, vitamin C and vitamin E) might reduce the effects of so-called
“free radicals,” a byproduct of hard endurance exercise. However this is still
a controversial view and the jury is currently out as to whether free radicals
actually pose a health risk in the majority of the population.
- Branched Chain Amino Acids (BCAA), like leucine and isoleucine, taken in doses of
5 to 20 grams per day may help prevent mental fatigue but the research is
inconclusive. Some studies show improvement in steady-state endurance performance—like
a 25-mile bicycle time trial. BCAAs have caused intestinal distress in some athletes.
Their use is currently legal.
Waste of Time and Money
- CLA (conjugated linoleic acid). A derivative of safflower oil, CLA is promoted as
a fat-burning, muscle-toning, energy-boosting agent. However the only study conducted
so far was done on rats. There have been no human studies.
- Inosine is a dietary supplement that supposedly improves endurance performance.
Several studies, however, indicate that it actually impairs performance in anaerobic
efforts like the sprint at the end of a bike race. It’s legal but may increase
risk for arthritis.
Potentially Harmful
- Amino Acids. These substances, like arginine, lysine and ornithine are supposed to
increase muscle mass and decrease body fat. However their use often leads to
intestinal distress and, if taken as supplements, they can block the absorption of
amino acids from food. They are legal but no studies indicate any performance
benefit.
- Bee Pollen. Many people are allergic to bee pollen and its use can lead to many
adverse reactions including anaphylaxis, a life-threatening medical emergency.
- Chromium. A popular supplement for a number of years, chromium is found naturally
in foods and is supposed to increase muscle mass and reduce body fat. Animal
studies show that it works but the results in studies with humans are not as clear.
High levels of supplementation may lead to chromium accumulation in the body and
studies with animals have shown some DNA damage at these levels although we aren’t
sure if this occurs in humans.
- DHEA is a steroid that is naturally secreted by the adrenal glands. When taken as
a supplement, it’s broken down into estrogen and testosterone, the “male” hormone.
Because it breaks down into testosterone, it’s appealing to body builders but
there’s no solid evidence that DHEA supplementation actually builds muscle. And
like all anabolic steroids, side effects may include excessive hair growth in women
and breast enlargement in men.
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