Caffeine for Sport
by GRP Dietician Megan Chacosky
Whether your workout is focusing on strength, power, speed, or endurance, you might have considered the intentional (or even accidental) use of caffeine as a performance enhancer. While there can be many confounding factors to choosing supplemental nutrition elements that meet the standards of being well-researched, safe for regular consumption, and proven to be effective in a variety of sport settings, caffeine continues to pass all of the tests as a potential high quality training companion. Touted for its ability to increase cognitive functions, such as sustained concentration, focus, decision-making and reaction time, caffeine is frequently linked to improved physical performances in most areas of sport, including repeated sprints, max strength or power, and middle- and longer-distance endurance events in almost every modality.
Biochemically, caffeine typically acts as a stimulator of the central nervous system (CNS) - commonly referred to as “the body’s processing center” - which can upregulate feelings of alertness while performing mentally or physically demanding activities, especially if the caffeine was consumed while in a state of fatigue, drowsiness, or stress. Not everyone naturally reacts to caffeine with this cognitive boost, though, with about 10% of the population dubbed innate non-responders, and a greater percentage of habitual caffeine consumers who have built up a tolerance to their usual effective dose over time. Decades of research in active and athlete populations teaches us that while caffeine can be combined with most training programs and lead to performance benefits, the real science boils down to determining your personal effective dose, and recovery goals, so your CNS is stimulated in a timely manner for exercise but calmed down quickly enough to not disturb rest or sleep (which also play incredibly important roles in training quality).
Some key factors to account for:
You always want to start with the lowest effective dose of ANY supplement; this will help reduce the risk of experiencing possible adverse effects (such as increased blood pressure, jitteriness, anxiety, diuresis/dehydration, or delayed parasympathetic nervous system activation that are possible with elevated caffeine doses).
For most people who respond to caffeine, this equates to ~0.45-2.72 mg/pound body weight.
1.36-2.72 mg/pound body weight has been shown to be most effective for sprint events.
50-300mg total (not per body weight) has been researched to best support endurance events.
Dosing is most effective ~30-60 minutes before physical activity lasting less than 2-3 hours.
For longer endurance events (those lasting > 4-5 hours), there might be additional benefit from using small doses of caffeine before the event and about halfway in.
In addition to your personalized response, the peak level of caffeine in your system will also be affected by the form of caffeine you use and recent food/meal intake.
Liquid or food forms of caffeine (e.g. coffee, tea, or supplements mixed with fluids) will absorb slightly faster than capsule forms.
Food intake, especially higher fiber, fat, or protein, can slow down the digestion rate of caffeine in the gut; but consuming caffeine on an empty stomach can reduce appetite and deter adequate intake of nutrients like carbohydrates needed for peak performance.
A critical clarification when considering caffeine as part of your training nutrition plan is to remember that caffeine increases the perception of energy - it doesn't actually give you direct energy; any caffeine supplementation plan needs to build from a foundation of adequate dietary intake, especially carbohydrates and water, to fully maximize its beneficial effects.
Natural forms, such as coffee and tea, can be simpler (and less expensive) to consume on a regular basis, but often have high variability in total caffeine content each brew. If you’re aiming for a more consistent and specific form of caffeine, look through the table below for safe-for-sport, high quality options to compare with natural choices.
Whenever possible, aim to stop caffeine consumption as early in the day as you can, ideally leaving no less than 6-8 hours of time between your last dose and when you plan to sleep.
The average half-life of caffeine is about 4 hours (with a total range of 2-8 hours in individuals), meaning that if you take 200mg of caffeine at 8:00am, on average you will still have ~100mg circulating in your system and providing CNS stimulation by noon.
With all of these tips in mind, the best advice for any sport nutrition tactic is to first practice how you will compete. If you’re used to consuming caffeine before or during training already, first check if your estimated dose falls within the recommended range as an “effective” dosing for you; if you can still increase caffeine to aim for potentially greater performance benefits safely and want to see how that feels, start with a small dose or form change to your caffeine source over multiple practice sessions before race day. If you’re not used to consuming caffeine in any form and are interested in seeing how it affects your performance, try small doses in a form that feels like the best fit for you during practice sessions before adding it to a race day plan.
