Once the first half marathon or marathon is completed, many runners shift their goal from “can I run this distance” to “how fast can I run this distance.” With the goal of running faster, we runners strive to optimize every aspect of our training. A sound training plan, good nutrition, and a smart race day strategy are all key to improving as a runner. The desire to become faster can focus on the very small details of these areas, such as a fat loading phase, beet juice supplementation, or a caffeine fast before a race.
One question I hear again and again from the runners I coach is about caffeine fasting before a marathon. First-time marathoners and Boston Qualifiers alike have inquired if they should abstain from caffeine before a race in order to run their best marathon. Is it worthwhile for an age group competitor or recreational runner do a caffeine fast before a race?
What is a Caffeine Fast?
Caffeine, particularly coffee and tea, is perhaps the most powerful legal performance enhancers for endurance athletes. Caffeine not only helps you feel more awake and alert on race morning; caffeine reduces perceived effort and improves running performance.
A caffeine fast before a race, especially a marathon, is a typical practice amongst elite runners and is becoming more popular in the ranks of age group competitors and recreational runners. A runner abstains from coffee, tea, and other forms of caffeine (including chocolate) for one week leading up to a race. He/she breaks the fast and consumes caffeine on race day and experiences enhanced performance from the caffeine.
Some of the practices of elite runners that have dripped down to the recreational level are valuable for all runners, such as doing a majority of your runs at a truly easy pace and eating enough food on a high-quality diet. Is a caffeine fast one of those practices that is worth recreational runners adapting before their next race?
Personally, I have never done a caffeine fast before a race. I’ve been a daily coffee drinker since the age of eighteen, so the idea of a caffeine fast before a race sounds miserable. The combination of the taper and pre-race nerves can be rough – why add caffeine deprivation to the equation as well? I have never attempted a caffeine fast because no finish time is worth a loss in productivity or altered mood for me.
The theory behind a caffeine fast is that habituation to regular caffeine consumption makes you less sensitive to caffeine’s effect, therefore also diminishing the performance boost from caffeine. The body does certainly adapt to caffeine consumption as the brain becomes less sensitive to caffeine’s effect. Habitual coffee drinkers, for example, need to drink more coffee to feel alert compared to non-coffee drinkers, who may feel jittery after just half of a cup.
A 2002 study in the Journal of Applied Physiology on the timing of caffeine ingestion before exercise found that non-users experienced greater improvements in exercise time to exhaustion and felt the effects of caffeine for longer than compared to caffeine users (all subjects ingested 5 mg of caffeine per kg of bodyweight). In order to get the maximal benefits from caffeine on race day, the one must be a caffeine non-user – at least for a week.
Does A Caffeine Fast Really Work?
Recently, the Journal of Applied Physiology published a study on the impact of habitual caffeine consumption on the performance response to caffeine. The researchers behind this study sought to determine the efficacy of a caffeine fast through one of the most rigorous studies yet. They divided 40 cyclists into three groups: low caffeine consumers, moderate consumers, and high consumers. Each group then performed three separate time trials: with caffeine, with a placebo, and with no caffeine.
A majority of the athletes saw significant improvements in their time trial with caffeine than with the placebo or no caffeine. Some athletes didn’t see any difference or negatively responded to the caffeine – but those individuals were not isolated to one of the control groups. A minority of individuals do not respond well to the combination of caffeine or exercise, regardless of their normal caffeine consumption.
In the majority of athletes who saw improvements in their athletic performance from the caffeine, the moderate and high caffeine consumers saw the same percentage of improvement in their performance as the low caffeine consumers. The study concluded that habitual caffeine consumption does not make a difference in the performance boost of caffeine. So, if you love your daily cup of coffee and want an extra boost on race day, you can still keep drinking your coffee as normal.
Should You Do a Caffeine Fast?
Ultimately, every runner responds to stimuli differently – including caffeine. The advice I always give my runners to consider how they function without caffeine. The side effects of a caffeine fast include headache, irritability, and drowsiness. If you struggle without a daily cup, then know that a caffeine fast will not have a noticeable impact on your race times, but it will have a noticeable effect on your daily life beyond running.
Always be mindful of the placebo effect with any type of supplementation. A caffeine fast may not make a difference in your body’s response to caffeine, but your belief in the caffeine fast might lead to a beneficial effect.
If you do choose to try a caffeine fast, do not do so before your goal race without practicing it in training or before another race. Reducing your caffeine tolerance to that of a non-user could result in experiencing the negative impacts of caffeine such as lightheadedness, dizziness, or GI upset.
Most of all, remember that when an elite runner does a caffeine fast, it is because seconds matter for their success in a race – and therefore their paycheck. For a majority of runners, your livelihood is not determined by the time on the clock of your next race. And most of all, remember no caffeine fast or supplementation is a replacement for training hard.
Have you ever done a caffeine fast before a race? How did it affect you?
Receive Weekly Running Tips & Motivation
Subscribe for my weekly newsletter and receive a free download of injury prevention exercises for runners.