Caffeine ingestion has well-established beneficial effects for resistance exercise performance. Caffeine is recognised by the International Olympic Committee (IOC) as one of five dietary supplements with good to strong evidence that it can improve exercise capacity and performance. A substantial body of meta-analytical data shows that acute caffeine intake, at doses of 3–6 mg/kg body mass (BM), exerts an ergogenic effect in exercises performed over a wide range of durations and intensities, which explains why approximately 76% of athletes consume it for competition1.
A 2022 meta-analysis of 12 studies on the minimum effective caffeine dose revealed an ergogenic effect of caffeine for muscular strength, muscular endurance and mean velocity. The magnitude of these effects was similar to previously reported higher caffeine doses, suggesting that much lower doses of 1-2 cups (or 1-2mg of caffeine per kg of body weight) ingested through an everyday diet have the same benefit2.
A large meta-analysis of 21 studies in 2020, suggested that caffeine improves performance in a range of exercise tasks, including muscle endurance and muscle strength. This review also suggests that the effect on aerobic performance (longer duration) seems to be greater than anaerobic exercise (quick bursts). In fact, aerobic endurance appears to have the most consistent moderate-to-large benefits from caffeine use3.
A 2022 review of the safety of caffeine in athletes concluded that using approximately 3.0 mg/kg of caffeine, provided the ergogenic benefits of caffeine with the lowest impact of other effects such as sleep disturbance4. This is in line with EFSA’s Scientific Opinion on the Safety of Caffeine which concluded that ‘single doses of caffeine up to 200mg (about 3mg/per kg of body weight) from all sources does not raise safety concerns for the general adult population, even if consumed less than two hours prior to intense physical exercise under normal environmental conditions5.
In 2021, the International Society of Sports Nutrition (ISSN) updated its position statement on caffeine and exercise performance to support the view that supplementation with caffeine can enhance various aspects of exercise performance6. The position statement concludes that the benefits of small-to-moderate* amounts of caffeine use include: improved muscular endurance, movement velocity and muscular strength, sprinting, jumping and throwing performance, as well as a wide range of aerobic and anaerobic sport-specific actions6.
Dr Neil Clarke PhD, Course Director for MSc. Sports and Exercise Nutrition at Coventry University, commented: “Caffeine ingestion has consistently been shown to improve endurance, high-intensity and resistance exercise, as well as intermittent sports such as football and tennis. Similarly, cognitive function, including attention and vigilance have also been shown to be improved following caffeine ingestion. These beneficial effects are generally independent of training status, habitual caffeine intake, and sex. In addition, there is growing evidence that coffee is an equally effective alternative to caffeine powder or tablets for improving exercise performance. Furthermore, data suggest that coffee, when consumed in moderation, contributes to daily fluid requirement and does not pose a detrimental effect to fluid balance.”
Examples of how coffee and caffeine impact on sporting performance are described below.
Improvements in performance for middle-distance runners
A study on a group of amateur runners from 2019, exploring the effects of alternate forms of caffeine supplements, supports the evidence for improved performance during aerobic exercise. Although individual results differed, the overall findings showed that irrespective of delivery form, a moderate dose of caffeine supplementation produces worthwhile gains in 5km running performance vs. placebo7.
Coffee’s impact on alertness and reaction time in sport
A 2022 review concluded that where alertness and attention are critical to sports performance, low or moderate intakes of caffeine before and/or during exercise can help improve aspects of cognitive function that are likely to be important in that sports performance. Specifically, the researchers suggested that caffeine can improve reported levels of energy, mood and attention and may also improve simple reaction time, memory and fatigue8.
Sports performance benefits clear for both regular and occasional coffee drinkers
Caffeine intake could benefit those who drink coffee regularly, as well as those who only drink it occasionally. This is suggested by one 2020 study of resistance exercise and jumping9 and 2020 another study on cyclists undertaking a 5km cycling time trial10, with both studies suggesting improvements in regular caffeine users and low caffeine users by a similar amount.
Coffee consumption supports hydration in athletes
Hydration is important in athletes. Whilst caffeine itself may have a mild diuretic effect, the contribution to overall fluid intake from a cup of coffee is notable. A 2016 study to try and develop a beverage hydration index (BHI)** found no difference between the cumulative urine output at 4 hours after ingestion of coffee and plain water, suggesting that coffee has the same short-term hydration potential as water when ingested in a dehydrated state11.
Improved performance for trained male runners
Additionally, a study has also shown that drinking a strong cup of coffee an hour before a competitive one mile (1.6km) running race can improve performance times in trained male runners by almost 2%. In the double-blind, randomised, crossover, placebo-controlled study, when caffeinated coffee was consumed, a race was completed approximately five seconds faster than when a placebo was consumed, and approximately four seconds faster than when decaffeinated coffee was consumed12.
Coffee caffeine and recovery
A 2022 study considered whether the combination of coffee with the recommended amount of carbohydrates may support post-exercise muscle recovery following an exercise session in endurance athletes. The authors concluded that the addition of coffee to sweetened milk increased muscle glycogen resynthesis during the 4-hour recovery period after an exhaustive cycling exercise. However, further research is required to investigate these associations13.
Tennis performance and accuracy
As the tennis season approaches athletes will be refining their training as well as nutrition support. A small study published in 2019 concluded that following intake of caffeine there was no observed impairment in serve accuracy, and some evidence of reduced fatigue in players, suggesting that caffeine may be helpful for tennis athletes14. The authors recommended that further work is needed in this area, however the work on caffeine and hydration status is relevant for tennis players as matches occur often during warmer months and may go on longer in order to reach a conclusion.
Enhancement to footballers’ physical performance
A 2019 review suggests that caffeine, ingested 5-60 mins before football practice, might produce valuable improvements to footballers’ physical performance. These improvements included jump performance, and repeated sprinting and running distance. The researchers also noted that caffeine does not seem to cause increased markers of muscle damage or changes in perceived exertion during football practice15.
Another 2020 study found that caffeine, at a certain dose, was effective in improving time to exhaustion, countermovement jump (CMJ) height, and rating of perceived exertion (RPE) of male football players, in atrial simulating the cardiovascular demands of a football game, regardless of differences in cardiorespiratory or neuromuscular fitness16.
Although some findings are encouraging, this is an area where more research needs to be done.
For further insights visit www.coffeeandhealth.org, a science-based resource developed for healthcare and other professional audiences that provides the latest information and research into coffee, caffeine and health.