Sports performance: Factsheet

Caffeine as an ergogenic aid

• Caffeine can have an ergogenic effect, meaning it can improve physical performance.
• Caffeine’s effect is most evident in endurance (aerobic) sports which last for more than five minutes. Caffeine appears to improve time-trial performance^2,3 and reduce muscle pain⁴.
• The European Food Safety Authority (EFSA) has stated that a cause and effect relationship has been established for caffeine intake and increased endurance performance (3mg/kg body weight 1 hour before exercise), endurance capacity (3mg/kg body weight 1 hour before exercise), and a reduction in perceived exertion (4mg/kg body weight 1 hour before exercise5. EFSA, in its 2015 Scientific Opinion on the Safety of Caffeine, concluded that single doses of caffeine up to 200mg (about 3mg/kg bw) from all sources do not raise safety concerns for the general adult population, even if consumed less than two hours prior to intense physical exercise under normal environmental conditions⁶.
• Although caffeine also appears to improve performance in certain types of short-term, high intensity (anaerobic) exercise in specific groups such as trained athletes performing intermittent exercises and team sports⁷, the overall evidence on the effect of caffeine on anaerobic activities remains inconclusive. EFSA does not currently consider there to be sufficient published science to support a cause and effect relationship⁵.
• In both cases, caffeine most likely exerts its effects via a pathway that leads to an increased production of adrenalin, which stimulates energy production and improves blood flow to the muscles and the heart^2,8.
• Caffeine may also moderate fatigue and influence ratings of exertion, perceived pain and energy levels, all of which are likely to lead to improvements in performance³.
• Fluid balance is critical in sports performance, and although caffeine can have a slight diuretic effect, the benefit of fluid intake from a cup of caffeineated coffee outweights the small diuretic effect and contributes to overall fluid requirements. Statements advising the avoidance of caffeinated beverages before and during exercise are unfounded⁹.