Caffeine and Exercise

Bridge et al. (2006) reported on a randomized controlled trial testing the effect of caffeine vs. placebo on for competitive runners on an 8 km race.  They were given either 3 mg per kg of their body mass of caffeine, or a placebo capsule consisting of 3 mg per kg body mass of glucose, one hour before the warmups for the race started.  They found that those ingesting the caffeine improved their times by an average of 23.8 seconds.  The improvement varied from 10 seconds to 61 seconds, so the authors suggest that some athletes may exhibit a greater response to caffeine than others, and this should be taken into account when making a recommendation to use caffeine before an event.  Athletes could test it out to see if it seems to work for them. 

 

Stadheim et al. (2013) reported on a randomized controlled trial with competitive cross country skiers using the double-poling technique. These athletes ingested 6 mg/kg body weight caffeine or placebo, 75 minutes before an 8 km race, and those taking the caffeine saw their time improve by an average of a minute 25 seconds.  The authors note that this was the difference between first place and 12^th place in a 15 km world championship race, so an improvement of this magnitude would be quite meaningful. 

 

A 2021 study by Stadheim et al. investigated whether oxygen uptake could be the mechanism by which caffeine was improving performance.  Being able to get more oxygen into the muscles would allow them to perform work more efficiently.  These trained athletes were given either 4.5 mg/kg body or placebo, 45 minutes before their warmup.  They then had to run on an inclined treadmill until exhaustion as the speed of the treadmill continued to increase.  They found that they were able to run for an average of 20 seconds longer when given the caffeine than the placebo.  They also found that the rate of oxygen consumption was increased by caffeine, although this was only enough to explain 4 seconds worth of the increase in the length of time they were able to keep running.  All three of these studies also found that lactate was higher when caffeine was consumed, indicating that caffeine also affects anaerobic performance. 

 

While there may still be more to learn about how exactly caffeine is able to improve exercise performance, Davenport et al. (2020) studied the ideal timing for caffeine intake before exercise.  They found that ingesting the caffeine 35 minutes before starting the exercise worked better than waiting to ingest as exercise was commencing, or than waiting to ingest it once the more strenuous portion of the exercise was about to begin.  Another interesting study (Sarshin et al., 2020) looked at recreational athletes and found that ingesting caffeine 45 minutes before exercise resulted in a faster recovery time. 

 

References:

 

Bridge, C. A., & Jones, M. A. (2006). The effect of caffeine ingestion on 8 km run performance in a field setting. Journal of Sports Sciences, 24(4), 433–439. 

 

Davenport, A. D., Jameson, T. S. O., Kilroe, S. P., Monteyne, A. J., Pavis, G. F., Wall, B. T., Dirks, M. L., Alamdari, N., Mikus, C. R., & Stephens, F. B. (2020). A Randomised, Placebo-Controlled, Crossover Study Investigating the Optimal Timing of a Caffeine-Containing Supplement for Exercise Performance. Sports Medicine – Open, 6(1). 

 

Sarshin, A., Naderi, A., da Cruz, C. J. G., Feizolahi, F., Forbes, S. C., Candow, D. G., Mohammadgholian, E., Amiri, M., Jafari, N., Rahimi, A., Alijani, E., & Earnest, C. P. (2020). The effects of varying doses of caffeine on cardiac parasympathetic reactivation following an acute bout of anaerobic exercise in recreational athletes. Journal of the International Society of Sports Nutrition, 17(1). 

 

Stadheim, H. K., Kvamme, B., Olsen, R., Drevon, C. A., Ivy, J. L., & Jensen, J. (2013). Caffeine Increases Performance in Cross-Country Double-Poling Time Trial Exercise. Medicine & Science in Sports & Exercise, 45(11), 2175–2183. 

 

Stadheim, H. K., Stensrud, T., Brage, S., & Jensen, J. (2021). Caffeine Increases Exercise Performance, Maximal Oxygen Uptake, and Oxygen Deficit in Elite Male Endurance Athletes. Medicine and Science in Sports and Exercise, 53(11), 2264–2273.