Caffeine, the world’s most popular psychoactive agent, has been proven to increase alertness. It has also been proven to enhance performance in endurance athletes. That’s where the story gets a little murky, like a cup of coffee. And the protagonists on either side of the debate are fierce in their opinions.
Yes, caffeine improves performance in endurance athletes. Proponents of caffeine cite three ways that it promotes performance: mental alertness, improved fat mobilization and reduced perceived effort. You can see that one of these three is physiological, and two are mental.
It seems that most everyone is bought in on the idea that caffeine promotes alertness. Some users drink coffee to keep awake. In Steig Larsson’s novel The Girl with the Dragon Tattoo, at turning points in the story, usually at 1 A.M. or later, the key players all gather to figure out what to do—over coffee. It seems that these Swedish people are drinking coffee incessantly. So I asked my friend Anders Malmberg, who lives in Malmo, outside of Stockholm, if it’s really true that they drink coffee without ending in Sweden. Anders replied, “I guess they do drink a lot of coffee.” Ja, vi dricker jättemycket kaffe. Good luck with pronunciation,” says Anders. Michael Blomqvist, one of the main characters, at one point barks at his assistant, “My office. Now. And bring coffee.” Caffeine is sufficiently storied for its anti-drowsiness powers that there is even a piece of computer software that keeps your Macintosh from putting itself to sleep. The name of this software: Caffeine.
Caffeine actually does affect endurance performance physiologically. As with many things physiological, it’s a bit complicated. In essence, caffeine enhances your ability to access your fat stores, which delays depletion of muscle glycogen. That lets you hang on longer.
Caffeine does indeed lower rate of perceived exertion (RPE). That means you can go at a higher intensity than you think you are. Imagine that you ride the hill to Jamestown one day, and it feels really hard, but on another day feels really easy. Well, nobody really works that way. If it feels easy, you are like to go faster. As legendary cyclist Eddie Merxx has said, “It doesn’t get any easier. You just go faster.” So a lowered RPE gives you more headroom to work harder but not have to feel it as much.
So, the fans of caffeine say: what’s not to like about it? Caffeine makes you more alert, more potent, and more able to deal with the perception of how hard you are working. What’s wrong with that?
Those who don’t care for caffeine have their own story. Most of them acknowledge the three points above as being real and true. But dosage and administration of caffeine, the way most athletes do it, wash away all the gains. Here’s their reasoning.
Caffeine users become habituated to the affects fairly quickly. An athlete who does not ingest caffeine regularly will, if she takes some on board, find her pulse elevated and sense the caffeine in her system in other ways, such as sour stomach and jitters. An athlete who drinks caffeine regularly—not so much. While organizing myself for a ride up Mount Lemmon in Tucson, AZ this autumn, I chugged an energy drink as an experiment. I don’t drink coffee, so generally have zero caffeine in my system. A few minutes later, a car with two cyclists pulled up, also staging for the Mount Lemmon climb, and asked some directions. I pulled out a cycling map to point out some features of the ride, and my index finger was so jumpy that it looked like the needle on a seismograph in a Richter Scale 8 earthquake. To feel the positive effects of caffeine, you need to abstain at least four days before your event, otherwise, no bump, but maybe some jitters.
Some writers believe that the uptick in attention and performance from caffeine is really a relief from caffeine withdrawal, not actually a net gain on the positives. Caffeine users may feel withdrawal symptoms, such as headache and fatigue, as early as 18 hours after their last dose. The headache and fatigue may disappear with the next dose of caffeine and may feel like a boost, but may in reality be just getting back to zero.
While caffeine has been shown to enhance recovery by mobilizing fat and enabling replenishment of glycogen in the muscles, it also is famous for delaying sleep. With a six-hour half-life (six hours after ingesting 100 units of caffeine, 50 units are still active), caffeine may give you trouble sleeping even many hours after your last dose. Restoring muscle glycogen is a prime component of recovery, and caffeine helps with that. But sleep is the most important element of recovery, and caffeine works against that. So the recovery effects are a bit at odds with each other.
What’s the right answer?
If you want to use caffeine to improve your training or race results, you need to refrain from caffeine for many days in advance of the event, then administer caffeine a couple of hours before the event, and continue through the event, so as not to feel a lag. Some products, such as cola and some gels, have caffeine. A new sports drink, Zum XR, has caffeine in solution, but also features small spheres which release caffeine and electrolytes in a time-release fashion, similar to how pharmaceuticals are released. This extended release technology helps smooth out the peaks and valleys of caffeine in your system for the duration of the event. Unlike gels, Zum XR has a lot of fluid, so you don’t have to worry about having the wrong osmotic pressure in your digestive system, and the gastrointestinal impacts that may ensue.
Whatever your relationship with caffeine, to get the full ergogenic effects, you have to use caffeine deliberately. Double dosing your normal cuppa won’t do much to improve your performance.