Does caffeine before training help?
Short answer
A little. 3–6 mg per kg of body weight, usually about 60 minutes before, improved performance in studies; for maximal strength the effect was small. Late in the day, caffeine can disturb sleep.
Figures
- 3–6 mg/kg · usual effective dose (ISSN)
- 60 min · before, most common timing in studies
- 0.20 · effect size for maximal strength (Grgic 2018)
- 0.2 (95% CI: 0.03–0.36) effect size: Maximal strength
- 0.21 (95% CI: 0.02–0.39) effect size: Upper body
- 0.15 (95% CI: -0.05–0.34) effect size: Lower body
- 0.17 (95% CI: 0–0.34) effect size: Jump power
How much
The ISSN position stand names 3–6 mg per kg as consistently effective, so 240–480 mg at 80 kg. As little as 2 mg/kg may be enough. Very high doses such as 9 mg/kg often cause side effects and are not needed.
When
Caffeine was most often taken 60 minutes before training. According to the ISSN, caffeine gum may need a shorter wait than capsules. If you train in the evening, weigh the small performance gain against worse sleep.
Limits
People respond very differently, including with anxiety or sleep problems. Most studies were in young men. With heart conditions, in pregnancy or on medication, check caffeine with a doctor.
Sources
- Effects of caffeine intake on muscle strength and power: a systematic review and meta-analysis. · Grgic · 2018 · Journal of the International Society of Sports Nutrition PubMed DOI Study note
- International society of sports nutrition position stand: caffeine and exercise performance. · Guest · 2021 · Journal of the International Society of Sports Nutrition PubMed DOI
- Wake up and smell the coffee: caffeine supplementation and exercise performance-an umbrella review of 21 published meta-analyses. · Grgic · 2020 · British Journal of Sports Medicine PubMed DOI
Summaries by SetCtl, not medical advice.