Take 3–6 mg of caffeine per kg of bodyweight (about 1.4–2.7 mg per lb) 30–60 minutes before training. For a 180 lb lifter that is roughly 250–490 mg. It reliably adds a few percent of strength and more reps to failure. Stop 8–10 hours before bed to protect sleep.
Caffeine is a well-studied performance aid. It modestly improves strength, power and muscular endurance and lowers perceived effort.
3 mg/kg is the conservative effective dose, 6 mg/kg the upper end. Coffee is estimated at 95 mg per 8 oz cup. Values above 400 mg/day are flagged.
| Bodyweight | 3 mg/kg | 4.5 mg/kg | 6 mg/kg | ≈ cups of coffee (3 mg/kg) |
|---|---|---|---|---|
| 120 lb (54 kg) | 165 mg | 245 mg | 325 mg | 1.7 |
| 140 lb (64 kg) | 190 mg | 285 mg | 380 mg | 2.0 |
| 160 lb (73 kg) | 220 mg | 325 mg | 435 mg ⚠ | 2.3 |
| 180 lb (82 kg) | 245 mg | 365 mg | 490 mg ⚠ | 2.6 |
| 200 lb (91 kg) | 270 mg | 410 mg ⚠ | 545 mg ⚠ | 2.9 |
| 220 lb (100 kg) | 300 mg | 450 mg ⚠ | 600 mg ⚠ | 3.2 |
| 240 lb (109 kg) | 325 mg | 490 mg ⚠ | 655 mg ⚠ | 3.4 |
| 260 lb (118 kg) | 355 mg | 530 mg ⚠ | 710 mg ⚠ | 3.7 |
Where most of the evidence sits for strength and power.
Recommended pre-workout dose
245–408 mg
Take 30–60 minutes before your first heavy set.
Estimate only, not a prescription. Check with your doctor before taking any dose.
This is above the 400 mg/day generally considered safe for healthy adults. Stay at the lower end and count everything else you take that day.
0–15 min
Absorption starts
Caffeine is absorbed quickly from the gut. Gum and mouth-absorbed forms act faster.
30–60 min
Peak in blood
Blood levels peak. Start your heavy work sets in this window.
3–6 h
Half-life
Half the dose is still active. Large between-person differences due to genetics (CYP1A2).
8–10 h
Sleep cut-off
Enough remains to reduce deep sleep. Your last dose should be at least this long before bedtime.
| Outcome | Effect | Evidence |
|---|---|---|
| Max strength (1RM) | Small boost (≈ +2–3% on average) | Strong |
| Reps to failure | Small–moderate boost | Strong |
| Power & bar speed | Small boost | Strong |
| Perceived effort (RPE) | Lower at the same load | Strong |
| Muscle growth | Indirect only | Limited |
| Muscle soreness | Possibly reduced | Limited |
+ Exact dose, cheap, what most studies used.
− Easy to overdose with powder — never use a spoon.
+ Natural, cheap, works similarly in studies.
− Caffeine content varies a lot (60–200 mg per cup).
+ Convenient, often combined with citrulline or beta-alanine.
− Doses often high and blends unclear; check the label.
+ Fastest acting, good between attempts at a meet.
− Lower dose per piece, less studied for strength.
“Caffeine dehydrates you during training.”
Mostly falseAt normal doses the fluid in coffee offsets its mild diuretic effect, and regular users adapt. It does not meaningfully hurt hydration in a workout.
“You must quit caffeine for weeks before a meet for it to work.”
FalseStudies in habitual users still show performance gains. A short reduction can help some people, but a full detox is not required.
“More caffeine means more strength.”
FalseBenefits plateau around 6 mg/kg. Above that, jitters, heart rate and poor sleep rise faster than performance.
For: Most lifters training in the afternoon
For: Powerlifting competitors
Guest et al., J Int Soc Sports Nutr, 2021
For your training: This is the reference document. Dose by bodyweight, not by 'one coffee'.
Grgic et al., J Int Soc Sports Nutr, 2018
For your training: Expect a few extra pounds on your top set — meaningful for a meet, not a miracle.
Grgic et al., Br J Sports Med, 2019
For your training: Few supplements have evidence this broad. Caffeine is a safe default for most lifters.
Gonçalves et al., J Appl Physiol, 2017
For your training: No need to quit coffee before a competition — keep your routine.
Not necessary. Research shows regular users still get a performance boost from a pre-meet dose. Quitting mostly gives you withdrawal headaches during your peak week.
Around 3 mg per kg of bodyweight is a good start (about 270 mg for a 200 lb lifter), 30–60 minutes before training. Go up to 5–6 mg/kg only if you tolerate it well.
No meaningful effect at normal doses. Caffeinated drinks still count toward your fluid intake.
Yes. Early concerns about caffeine blunting creatine have not been confirmed in recent studies. Some people prefer to separate them for stomach comfort.
Not directly. It helps you do more reps and volume, which can support growth over time if your training and nutrition are in place.
Coffee works too, but its caffeine content varies a lot. Pills give a precise, repeatable dose, which matters on meet day.
Ranked by citations. Metadata from OpenAlex (CC0).
Mental health in elite athletes: International Olympic Committee consensus statement (2019) ↗
Claudia L. Reardon, Vincent Gouttebarge, Emily Kroshus et al. · British Journal of Sports Medicine · 2019 · 1,268 citations · Study · Open access
Skeletal muscle energy metabolism during exercise ↗
Mark Hargreaves, Lawrence L. Spriet · Nature Metabolism · 2020 · 1,230 citations · Study
François Maltais, Marc Decramer, Richard H. Casaburi et al. · American Journal of Respiratory and Critical Care Medicine · 2014 · 1,095 citations · Study · Open access
IOC consensus statement: dietary supplements and the high-performance athlete ↗
Ronald John Maughan, Louise M. Burke, Jiří Dvořák et al. · British Journal of Sports Medicine · 2018 · 995 citations · Study · Open access
ISSN exercise & sports nutrition review update: research & recommendations ↗
Chad M. Kerksick, Colin Wilborn, Michael D. Roberts et al. · Journal of the International Society of Sports Nutrition · 2018 · 943 citations · Review · Open access
Exercise management in type 1 diabetes: a consensus statement ↗
Michael Charles Riddell, IAN W. GALLEN, Carmel E. Smart et al. · The Lancet Diabetes & Endocrinology · 2017 · 901 citations · Study · Open access
International Olympic Committee consensus statement on youth athletic development ↗
Michael F. Bergeron, Margo Lynn Mountjoy, Neil Armstrong et al. · British Journal of Sports Medicine · 2015 · 883 citations · Study · Open access
The creatine kinase system and pleiotropic effects of creatine ↗
Theo Wallimann, Małgorzata Tokarska-Schlattner, Uwe Schlattner · Amino Acids · 2011 · 794 citations · Study · Open access
International society of sports nutrition position stand: caffeine and performance ↗
Erica R. Goldstein, Tim N. Ziegenfuss, Doug Kalman et al. · Journal of the International Society of Sports Nutrition · 2010 · 686 citations · Study · Open access
Muscle fatigue: general understanding and treatment ↗
Jing-jing Wan, Zhen Qin, Peng‐Yuan Wang et al. · Experimental & Molecular Medicine · 2017 · 677 citations · Study · Open access
International society of sports nutrition position stand: caffeine and exercise performance ↗
Nanci S. Guest, Trisha A. VanDusseldorp, Michael T. Nelson et al. · Journal of the International Society of Sports Nutrition · 2021 · 659 citations · Study · Open access
Caffeine: Cognitive and Physical Performance Enhancer or Psychoactive Drug? ↗
Simone Cappelletti, Daria Piacentino, Gabriele Sani et al. · Current Neuropharmacology · 2014 · 631 citations · Study · Open access
IOC Consensus Statement: Dietary Supplements and the High-Performance Athlete ↗
Ronald John Maughan, Louise M. Burke, Jiří Dvořák et al. · International Journal of Sport Nutrition and Exercise Metabolism · 2018 · 535 citations · Study · Open access
Mike Doherty, Paul M. Smith · Scandinavian Journal of Medicine and Science in Sports · 2005 · 515 citations · Study · Open access
Efficacy and Safety of Ephedra and Ephedrine for Weight Loss and Athletic Performance ↗
Paul Shekelle, Mary L Hardy, Sally C. Morton et al. · JAMA · 2003 · 513 citations · Study · Open access
Put the research into practice
Tozemoon is a free workout tracker: log every set, detect PRs and get AI coaching.
Tozemoon is not a medical provider, and its authors are not physicians, dietitians or licensed healthcare professionals. All content, calculators, tables and protocols on this site are provided for general information and education only. They are not medical, nutritional or health advice, diagnosis or treatment, and do not create any professional relationship.
Results from calculators are rough estimates based on published averages and may not apply to you. Individual responses to supplements, caffeine, diet, cold exposure and training vary widely, and some can be dangerous for people with heart, kidney, liver or blood pressure conditions, during pregnancy or breastfeeding, for minors, or when combined with medication.
Always consult your doctor or a qualified healthcare professional before acting on anything you read here. Never ignore professional medical advice or delay seeking it because of this content. If you experience chest pain, palpitations, dizziness or any worrying symptom, stop exercising and seek medical help immediately. You use this information at your own risk; Tozemoon accepts no liability for any consequence of its use.
How we write these guides: we rank studies by citations using OpenAlex, prioritise meta-analyses and position stands, and summarise them in our own words with links to every source. Educational summary, not medical advice. Consult a professional before changing your diet or supplementation.