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Mythbusting Caffeine Habituation
Introduction
Q: If I regularly use caffeine, will it still work when taken before and/or during exercise?
A: YES! You can keep your caffeine habit and still reap its benefits when you exercise.
The idea that habituation reduces caffeine’s effect on exercise performance is a myth that has been perpetrated by years of investigator reporting bias, unsupported anecdotal comments, and ambivalent study designs in many peer-reviewed articles over the years.
The real story is that no matter how much caffeine you normally ingest daily, taking it before and during exercise will still produce tangible performance benefits – or, in scientific terms, it’ll still be ergogenic. You will still run faster, farther, longer, burn more fat, spare more glycogen, and perform better physically if you ingest caffeine before exercise. Your physiology and biochemistry still respond favorably to caffeine and always have. So keep it up!
The clincher
The question of habituation making supplemental caffeine less effective or useless for exercise performance has finally received direct, cogent scrutiny from sports researchers. The clinching argument refuting habituation is a recent meta-analysis and systematic review (Carvaljo 2022). This study looked at 60 human studies on caffeine-habituated women and men doing endurance, power and strength exercises, including both trained and untrained individuals. It compared caffeine supplemented results with placebo groups. Despite the proliferation of caffeinated exercise supplements, nobody else has examined this totality of evidence yet.
The caffeine effect examined was exercise performance, also called ergogenesis, demonstrating that whatever type of exercise you do, you can do more of it or do it more efficiently with caffeine than without. The effects were universal, regardless of caffeine source, exercise type, sex, or athlete proficiency. This worked for coffee and for caffeinated pills, foods, and drinks. The type of exercise did not matter – endurance, power, and strength exercises all benefited from acute caffeine supplementation. Both women and men benefited from caffeine, and both trained and untrained persons showed benefits.
Dosage Matters
Whether you take more or less caffeine than you habitually consume per day, caffeine supplementation still worked to enhance performance compared to no caffeine. Was this possibly because the placebo group went downhill from caffeine withdrawal effects? No! Withdrawal periods from caffeine of less than 24 hours, 24-48 hours, and more than 48 hours (complete withdrawal) did not change the effect of pre-exercise caffeine. No matter how somebody may have felt, their bodies still responded to caffeine.
The only limit found was caffeine dose. Doses under 3mg/kg (~200mg) worked fine, as did doses between 3-6mg/kg (up to ~400mg at a time). The average improvements across the board were ~26%. But doses over 6mg/kg (500mg and up) showed a smaller improvement, around 11%, which was not statistically significant (p=0.23, compared to p=0.003 & p=0.0001 for <3 and 3-6 mg/kg doses).
Long-time reviewers of sports ergogenics have already known that high doses of caffeine are often not helpful, so this re-analysis confirmed our observations that there can be too much caffeine (500mg or more).
The First Endurance caffeine strategy
First Endurance has structured caffeine dosing accordingly, formulating PreRace to bring your body up to that ideal 3mg/kg range before you begin a session or race. As suggested by our own research and demonstrated in the meta-analysis cited above, this dose works just as well as higher doses and actually works better than extreme doses over 500mg. It was obvious when you look at the totality of evidence (dozens and dozens of human studies since the 1940s), and only confirmed by this latest meta-analysis.
The caffeinated Kona Mocha Liquid Shot serves a different purpose: maintenance of already ideal caffeine levels, not for amping the body up to those ideal levels. Given that role, we formulated Kona Mocha LS with just 25mg of caffeine (far less than typical caffeinated gels, which sit in the 80-100mg range) in order to account for frequency of use, your body’s metabolization of caffeine, and the diminishing returns once caffeine loads exceeds 6mg/kg of body weight.
That 25mg mark lets you continue using Liquid Shot for fuel during multi-hour events without taking on an additional 100mg of caffeine every 30 minutes to an hour – a rate that quickly buries the needle in the red zone of negative returns. It’s about effectively maintaining carb supply and caffeine supply. (See this article by Dr. Matt Hanson, who is habituated to winning IRONMAN championships, for more on using Kona Mocha Liquid Shot to maintain caffeine levels.)
On responders and non-responders
Some people either don’t do well with caffeine or experience less benefit. It’s genetic. They may have less ability to metabolize caffeine (CYP1A2 gene) and/or have their adenosine receptors blocked less than normal (ADORA2A gene). Sufficient research has been conducted on these two genetic polymorphisms; they have not found these two genetic differences to affect exercise performance adversely, especially within the range of 3mg/kg caffeine levels.
How did so many get habituation so wrong?
Research is not easy, and smart folks can read more into findings than is really there – that’s what we are trained to do! But the myth of caffeine habituation hampering caffeine effects when you exercise may have something to do with mood at the higher doses. These high-dose studies tended to find more mental fallout, which detracted from fine motor skills, a level-headedness, and keeping your mind under control. Also, their conclusions aren’t completely wrong. Yes, you can get too much caffeine (500mg mega doses or exceeding 6mg/kg of body weight); however there is an ideal zone (3-6mg/kg) that nets tangible benefits without the negative impacts of overdosing – but again, that’s about dosage, not habituation.
Summary
This meta-analysis’ conclusion only stated the obvious that was disbelieved by some: that caffeine works to improve exercise performance for almost everyone if you do not take too much. (That conclusion also holds true for water, carbs, fat, and even electrolytes.) The trick is to get your body into that target range of 3mg/kg, and – for endurance events that last longer than the ability of caffeine to stay at effective doses in your body (between 2-6 hours) – use additional doses to maintain the full effect without pushing past the 6mg/kg limit. As always, try out interventions during training to fine tune what feels best for you – after all, no body is exactly alike.
References
Carvalho A, Marticorena FM, Grecco BH, Barreto G, Saunders B. Can I have my coffee and drink it? A systematic review and meta-analysis to determine whether habitual caffeine consumption affects the ergogenic effect of caffeine. Sports Med. 2022 May10, DOI: 10.1007/s40279-022-01685-0
