Caffeine is the core ingredient in most pre-workouts. Two meta-analyses show how much it helps your lifts and that you may not need a high dose.
Strength, endurance and bar speed
A 2022 meta-analysis in Nutrition looked at the smallest effective caffeine doses for resistance exercise. It found an ergogenic effect on muscular strength (effect size about 0.17), muscular endurance (about 0.21) and mean bar velocity (about 0.56), even at very low doses. The authors concluded the minimum effective dose is lower than previously thought and that these amounts can be obtained from everyday sources such as coffee.
Movement speed
A 2020 meta-analysis of 12 studies in Sports Medicine found acute caffeine supplementation improved movement velocity in resistance exercise (pooled effect about 0.62). It helped at low, moderate and high loads, for both mean and peak velocity, and in upper- and lower-body exercises.
Using caffeine wisely
- Start low and see how you feel before adding more.
- Avoid caffeine late in the day if it hurts your sleep, since sleep drives recovery.
- Count caffeine from all sources, including energy drinks and pre-workout.
- Speak to a doctor if you are pregnant, have a heart condition or take medication.
For product safety see our pre-workout safety guide.
Frequently asked questions
Does caffeine improve strength?
A 2022 meta-analysis found a small ergogenic effect on muscular strength and larger effects on endurance and mean velocity.
Do I need a big dose of caffeine?
The 2022 analysis found very low doses were ergogenic and similar in magnitude to higher doses.
Does caffeine help for heavy lifts too?
The 2020 meta-analysis found velocity improvements at low, moderate and high loads.
References
- Grgic J, Mikulic P (2022). Exploring the minimum ergogenic dose of caffeine on resistance exercise performance: A meta-analytic approach. Nutrition. PubMed 35203046
- Raya-González J et al. (2020). Acute Effects of Caffeine Supplementation on Movement Velocity in Resistance Exercise: A Systematic Review and Meta-analysis. Sports Med. PubMed 31643020
General information, not medical advice. Check with a doctor before starting a new training or supplement routine. Last updated 27 October 2026.
