Pre-training caffeine dose that reliably improves strength and endurance output.
An umbrella review of 21 meta-analyses found caffeine at 3–6 mg per kg of bodyweight, taken 30–60 minutes before training, produced small-to-moderate improvements in strength, power, endurance and muscular endurance.
What the researchers did
Grgic and colleagues aggregated 21 published meta-analyses covering hundreds of trials on caffeine and exercise performance across cardio, strength and team-sport contexts.
The key finding
3–6 mg/kg reliably beat placebo across nearly every outcome. Above 6 mg/kg the benefit stopped increasing while side effects (jitters, GI distress, poor sleep) rose sharply. Habitual coffee drinkers still get the ergogenic effect.
Why it matters
For a 75 kg person that is roughly 225–450 mg — about 2–4 espressos or one strong pre-workout serving, ideally 45 minutes before your hard set.
3–6 mg/kg 30–60 min pre-training. Skip it within 8 hours of bedtime to protect sleep.
- 1.6–2.2Daily protein intake that maximises hypertrophy.
- 7–9Nightly sleep for recovery, hormones and growth hormone release.
- 8,000Daily step count where all-cause mortality risk levels off — largely a NEAT effect.
- 3–5Creatine monohydrate dose — no loading needed.
- 25–38Daily fibre intake linked to lower all-cause mortality and a healthier gut microbiome.
- 10–20Hard working sets per muscle per week for hypertrophy.