Research

Hormonal

Caffeine ingestion (5 mg/kg) significantly increases time to exhaustion and oxygen deficit during supramaximal anaerobic exercise (MAOD test) by enhancing skeletal muscle metabolism and epinephrine release, rather than just CNS arousal.

Take 5 mg of caffeine per kg of body weight 90 minutes before a high-intensity, short-duration effort (like a hard cycling sprint to exhaustion). You can expect to last about 8% longer. This works by boosting adrenaline, which helps your muscles produce energy anaerobically. This benefit applies even if you drink coffee regularly.

GoodSupportsHIGH confidence
Caffeine increased time to exhaustion and O2 deficit during the MAOD test... The enhanced time to exhaustion might suggest that the effect of the caffeine treatments in the current study is related to an enhanced stimulation of skeletal muscle metabolism rather than stimulation of the CNS.
Douglas G. Bell et al. · Medicine & Science in Sports & Exercise · 2001

Why this rating

Randomized, double-blind, placebo-controlled trial with clear statistical significance.

Source

Effect of caffeine and ephedrine ingestion on anaerobic exercise performance

Douglas G. Bell et al. · Medicine & Science in Sports & Exercise · 2001

DOI 10.1097/00005768-200108000-00024

crossover · n=24Cited 190×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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