Powering through the final miles of a long-distance race can be a monumental task—although you’ve likely trained well to race hard to the line, it’s arduous for your brain to command your legs to maintain that speed and postpone reaction to exhaustion. Luckily, runners most everywhere have easy access to caffeine, a legal (World Anti-Doping Agency-approved since January 2004) stimulant that can increase performance in endurance athletes with proper implementation.
The benefit of caffeine in shorter distances is less significant than endurance events, but it does seem to have even mild ergogenic potential for events lasting more than one minute. Because caffeine can enhance alertness, runners who participate in shorter events may find the improved concentration useful in responding to the gun or getting out of start blocks. On the contrary, a fidgety response could contribute to a false start.
Caffeine is absorbed quickly and reaches its highest blood concentration in about an hour, and this high concentration can be maintained for several hours. When taken an hour before a race, the ergogenic effect can last the duration of a 5K, 10K and even a marathon. To date, though, evidence supports that caffeine proves most useful for endurance events.
Reaction to caffeine differs according to the user—some feel they don’t respond to caffeine at all, while others suffer nausea, anxiety, tremors, headaches and even impaired performance after ingestion. Still, others find they’re more alert, energized, focused and experience a sense of ease in running effort. If you experience a negative reaction to caffeine during training, it’s obviously not a good choice for you during racing; however, if you’re able to tolerate caffeine, here are some tips on how to use it to your advantage.
How Much and When?
A little caffeine is often a habitual start or pick-me-up during the day; however, when daily caffeine consumption becomes so routine that a continuous IV would work just as well, some question whether the ergogenic effect may be dampened. According to a study published in the Journal of Applied Physiology, ergogenic response during endurance exercise is greater and lasts longer in nonusers versus users. We know caffeine doesn’t contribute to dehydration in habitual users, but it may be worth rationing its daily use to take advantage of its performance-boosting potential. Daily java drinkers could also experiment with restricting use for several days prior to a race, then ingesting caffeine one hour before the start of the race.
Taking higher doses doesn’t make for a greater response. Ingesting doses greater than 9 mg/kg doesn’t appear to boost performance any more than a moderate dose of 3-6 mg/kg. Even a dose as low as 1-3 mg/kg can be all that’s required to take advantage of caffeine’s ergogenic effects.
Since performance is not improved with greater doses of caffeine, the goal is to find the minimum dose of caffeine to ingest in order to achieve the desired positive response. The use, source and the exact amount of caffeine one should take to achieve the desired effect can depend on things like one’s level of conditioning, body size, personal preferences and general goals. The total amount of caffeine a 110-pound runner requires may not be quite enough for a larger 170-pound runner. Similarly, a well-trained runner may experience a greater response compared to a less-trained runner given the same amount of caffeine.
Consuming moderate amounts of caffeine combined with carbohydrates during a long-distance race could also aid performance. Another study published in the Journal of Applied Physiology reported the effect of adding different amounts of caffeine to a carbohydrate and electrolyte sports drink consumed by cyclists performing a long time trial. The study concluded that the addition of moderate amounts of caffeine (3.2 and 4.5 mg/kg) to a 7 percent carbohydrate-electrolyte drink (0.5 grams of carbohydrate per minute) significantly improved one-hour cycling time trial performance compared with a lower dose of caffeine (2.1 mg/kg) and the carbohydrate-electrolyte drink. Consuming a caffeinated carbohydrate-rich sports drink, gel, beans or gummies during a race may enhance performance by increasing intestinal carbohydrate absorption and exogenous carbohydrate oxidation. Increasing exogenous carbohydrate oxidation reduces the body’s reliance on carbohydrates stored in muscles and the liver.
Picking the Right Product
With so many different products on the market, how do we know where to start? First, keep in mind that caffeine is considered an herbal dietary supplement. The U.S. Food and Drug Administration does not verify caffeine content—this means that we should beware of manufacturer claims regarding the amount of caffeine present in a product.
There are many, many forms of caffeine to choose from: coffee, teas, sodas, pills, gums, gels and shots. Each of these products carry varied does of caffeine. It can be hard to determine the exact caffeine content in coffee because different brands and strength of coffee can create quite a range in the amount of caffeine it delivers. Other compounds present in coffee may negate some of the potential benefits of the caffeine it delivers; some researchers believe these chemicals could even impair performance in endurance athletes. Even if coffee is declared a less-than-ideal source of caffeine, some may benefit from the psychological boost their favorite cup of brew offers.
Gels are a very common source of caffeine for endurance events—most contain 20-50 mg of caffeine. Regular low doses of caffeine throughout a longer race can be just as beneficial as a single greater dose before the event. Energy drinks are often marketed as energizing sports drinks. However, they can lack important electrolytes and contain additional, potentially undesirable, ingredients compared to the standard sports drink. The caffeine dose from these products often comes with a heavy sugar load, particularly when serving size per container is not observed. Gums, pills and shots are more direct caffeine sources.
Caffeine should be tested in training—both before and during runs—to assess individual response. It’s better to err on the side of caution when considering the source, amount and use of caffeine before and during training and racing.
Jackie Dikos, R.D., is a 2:45 marathoner and mother of two.