Nutritional Pharmacology
For the Enlightened Athlete
Food as a drug…and drugs that affect nutrient disposition
Be Caffeinated!
Caffeine and endurance
There is a wealth of scientific data concerning caffeine and exercise performance (for review see 6,13,18,21). The drug has also been freely available in a variety of forms containing predictable doses for decades. Many readers are aware in a vague sense that caffeine can enhance performance. You may even use coffee or OTC stimulants as a "pick-me-up" before a long ride or tough training session. Athletes and coaches should long ago have mastered the correct use of such a common drug. It seems that few have obtained the information necessary to derive consistent results. The purpose of this article is to bridge the gap between research and application.
This is technology--scientific data are used as starting points, not the goal. I will attempt to outline just enough research information about caffeine to explain the rules of use that I have derived. I hope that you are able to understand and implement these guidelines to improve your own performance.
Maximizing caffeine's benefits
It is crucial to note that caffeine's ergogenic (performance enhancing) effects can be roughly divided into two components: metabolic and nervous14,23. The metabolic effect primarily involves providing more fuel to working muscles1. Caffeine stimulates the release of free fatty acids (FFAs) from stored triglycerides. Higher blood levels of FFAs spare muscle glycogen by increasing fat oxidation1,20. The result is the ability to maintain a higher power output and/or to delay exhaustion9,10.
Caffeine causes the nervous system to secrete greater amounts of catecholamines (noradrenalin and dopamine), hormones responsible for attention and arousal, improving focus and concentration. Stimulating the central nervous system may also increase muscle contractility. Researchers have observed that caffeine can increase power output in single maximal efforts2,7,15,17. Maximal efforts are unlikely to be improved simply by making more fuel available. This effect of caffeine is possibly related to alterations in the ability to recruit muscle fibers.
Two mechanisms--two doses?
Therefore there are at least two separate mechanisms by which caffeine can benefit your performance. The most important conclusion to draw immediately is that if these effects do not peak at the same time, then two doses of caffeine must be ingested to maximize the metabolic and CNS aspects23. This is the basis of my protocol.
In order to maximize performance take the first dose of caffeine four hours before the beginning of the (endurance) race. Take the second dose for CNS effects from 60 to 15 minutes before start time. Why the range? The longer the race and the worse your nerves, the closer to the race start.
In the first instance by waiting you allow the caffeine to reach peak levels about one hour in, which may be a more strategic than the same burst from the outset which might tend to make you override your pace. If, like me, you suffer from competition nerves (and stomach!) then holding on until the last minute will help you stay calmer when tension is useless; the act of competing "chews up" the excess adrenaline and diminishes the feelings of anxiety that might otherwise result from caffeine25.
Finding the correct dose
The beneficial effects have been found to occur at a dose of 3-6mg of caffeine per kilogram of body weight12. 3mg/kg is well tolerated and generally shows a positive effect, whereas higher and lower doses sometimes do not. I therefore recommend using two separate doses of 3mg/kg each, at 4 hours and 1 hour before your anticipated start.
To find your bodyweight in kilograms, divide your weight in pounds by 2.2. Multiply this number by 3 to find the size of your doses. If you are a regular user of caffeine, round up to the nearest 50 or 100mg, depending on the form you use. If you are not habituated to caffeine, round down. For example, if you weigh 150 pounds, this is approximately 68 kilograms. Your optimal ergogenic dose would therefore be 204mg of caffeine--round to 200mg for convenience.
Warning: Doses of caffeine higher than 5mg/kg have repeatedly been found to be equally or less effective than low doses!11,12,19 Some studies have shown a decrement in performance at higher doses, indicating that the side effects predominated over the positive ones at those doses. Hear me now, listen to me later--more caffeine is not better!
Given the above example, your pre-race strategy would be as follows: at breakfast eat minimal carbohydrate (try eggs and bacon in butter, for example). A high carbohydrate intake at this point will not increase your muscle glycogen levels appreciably. Carbs will negate the metabolic effect of caffeine by suppressing the use of fat for energy23. If you eat a high carbohydrate breakfast, this dose of caffeine is worthless--stick to using only the one-hour pre-race dose.
Eat breakfast about four hours before race start and take one 200mg caffeine tablet after eating--I recommend Ultra Pep-Back™ by Alva-Amco because it is easy on the stomach and has somewhat of a timed release effect which reduces jitters. For smaller increments use peppermint flavored chewable No-Doz™ available in 100mg tablets which can be broken for 50mg amounts. This product is also easy on the stomach--many caffeine pills are not, so beware of this ahead of time. Don't try something new on race day.
When you are within one hour of beginning the race, take the second 200mg caffeine tablet. At this point you are in a prime state to burn fat which will spare your glycogen at the outset of the race. This will leave you more fuel especially for the "kick" at the end. The second dose will enable you to put forth maximum effort by decreasing your perception of effort and increasing your attention, concentration, and ability to contract your muscles.
Coffee versus caffeine
Caffeine is the commonly identified active ingredient in coffee. Coffee contains compounds that are thermogenic 3,8 (create heat) and anti-ergogenic--that is, coffee causes your temperature to rise more and somewhat counteracts the performance increase that would occur with pure caffeine. Coffee will increase performance, just not as much as pure caffeine will.
An equivalent dose of caffeine as coffee will raise body temperature more than caffeine alone. Tolerance to the benefits of caffeine does not seem to occur at moderate levels of daily intake4,5,22, which means that you do not need to stop drinking coffee a week before the race in order to enjoy caffeine's benefits.
I recommend that you use coffee during training in order to enjoy some of the benefits of caffeine and accustom yourself to the stimulant effects. During competition, use pure caffeine as described above.
Good Luck!
Summary
• Caffeine improves performance in endurance athletes.
• Research has uncovered at least two separate ways in which caffeine enhances endurance.
• The two major beneficial effects of caffeine occur at two different times after intake.
• The metabolic effects of caffeine (increasing free fatty acids) peak about four hours after ingestion.
• The central nervous system effects (decreased perception of effort, increased muscle contractility) occur about one hour after dosing.
• In order for endurance athletes to maximize the ergogenic effect it is therefore necessary to take two divided doses before a race.
1. The first dose is taken three or four hours before race start.
2. The second dose is consumed one hour or less before beginning.
• Most research has confirmed benefits with less than 5mg of caffeine per pound of bodyweight. 3mg/kg has repeatedly been shown to be well tolerated and effective.
• To find your optimal dose of caffeine divide your bodyweight in pounds by 2.2. Multiply this by 3 and round to the nearest 50mg. Before races use this dose four hours before and one hour before start.
• I recommend using coffee during training but pure caffeine for competition. Two brands of caffeine pills I have used successfully are Ultra Pep-Back™ by Alva-Amco and peppermint flavored chewable No-Doz™.
©2003 by Brian Petty
References
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