The Core Diet Blog

The International Society of Sports Nutrition recently produced an updated position stand on caffeine and exercise performance.  And JUST in case you don’t have the time or energy to wade through all 37 pages of the report, we’ve summarized the high points, as related to endurance exercise/sport, below.  You can also readour last blog on caffeine or some additional tips and tricks!  

1)  Aerobic endurance is noted to be the form of exercise with the most consistent moderate-to-large benefits from caffeine use.  

2)  How it works: 

  • Caffeine appears to work in various parts of the body, but the most abundant evidence shows that its MAIN target is the central nervous system. 

  • Its primary benefits are a reduction in the rate of perceived exertion and muscle pain and possibly an increase in the ability of skeletal muscle to generate force.

3)  Dosage counts:

  • When consumed in doses of 3-6 mg/kg body mass, caffeine has been consistently shown to improve performance.  

  • Minimal effect doses remain unclear, but they may be as low as 2 mg/kg body mass. 

  • High doses beyond 9 mg/kg body mass do not appear to be required to elicit a benefit and are associated with a high incidence of side-effects.

4)  Timing:

  • The most common timing of caffeine supplementation is 60 minutes pre-workout or race, as it is believed that this is when plasma levels of caffeine are at maximal values.  

  • However, research now appears to agree that the most beneficial time to take caffeine is late in exercise or a race when fatigue is highest.  

  • A determinant of optimal timing of caffeine ingestion is the source of the caffeine. Caffeine chewing gums and capsules have been shown to work more quickly than other sources such as coffee or energy drinks.  

  • The average half-life (the amount of time it takes for the quantity of a substance ingested to be reduced to half in your system) of caffeine is 4-6 hours; however, it may range from 1.5 to 10 hours.

5)  Differences in response among individuals:

  • The amount of benefit, the rate of metabolism, and the severity of adverse effects (sleep disturbance or increased anxiety) can vary significantly among individuals. This is attributed to genetic variation associated with caffeine metabolism and possibly habitual caffeine intake.

  • Caffeine does NOT appear to be influenced by sex, age, VO2 max, or type of sport.

Much of this information isn’t entirely new or different.  The hottest and most heavily researched area in the current day is genetic variation and the effect this has on an individual’s response to caffeine.  Since most of us won’t undergo genetic testing to develop an individualized caffeine plan, experimenting with dosage, habitual intake, and timing will likely help determine how best to use caffeine in training and racing.  

Guest NS, Vandusseldorp TA, Nelson MT, et al. International society of sports nutrition position stand: caffeine and exercise performance. Journal of the International Society of Sports Nutrition. 2021;18(1). doi:10.1186/s12970-020-00383-4 

Your Company Name


Not ready to purchase?  Grab a discount or trial offer with us!  Just fill out the form below and we'll send you the details to take advantage NOW.