Caffeine before running: dose, timing and what the research says

The ISSN position stand says caffeine at 3–6 mg/kg of body mass has consistently improved exercise performance, most often taken about 60 minutes before. Responses vary, and higher doses bring more side effects.

By RunFast · Updated 30 October 2026 · 7 min read

For caffeine before running, the International Society of Sports Nutrition (ISSN) position stand says doses of 3–6 mg per kg of body mass have consistently improved exercise performance.¹ It adds that the most commonly used timing is 60 minutes before exercise.¹ Aerobic endurance appears to be the kind of exercise with the most consistent benefit.¹ An International Olympic Committee (IOC) consensus statement gives the same 3–6 mg/kg, as anhydrous caffeine, for high-performance athletes.²

Most of that research covers exercise in general, not running. A 2022 meta-analysis of running alone pooled 21 studies with 254 participants, 167 recreational and 87 trained runners.³ Of those participants, 220 were men and 19 were women.³

This guide is general information, not advice for your medical situation. The IOC statement says dose and timing should be tried in training before competition.² The side effects, and who should take care, are further down.

What the research says about caffeine and running

The ISSN position stand covers exercise performance across sports, not runners alone.¹ An umbrella review of 21 meta-analyses found that caffeine improves performance in a broad range of exercise tasks.⁴ It found the effect generally greater for aerobic than for anaerobic exercise.⁴ It rated the quality of the evidence as generally moderate, and most of the studies behind it were in young men.⁴

Running specifically

The 2022 running meta-analysis looked at two kinds of test. Time to exhaustion in running tests improved with caffeine, with a medium effect, in recreational and trained runners.³ The time to finish endurance running time trials was also reduced compared with a placebo, but the effect was small.³ Within trained runners, and within recreational runners, the time-trial benefit was not statistically significant.³

So the clearest result is in running for as long as you can at a fixed pace, not in covering a set distance faster.

How much, and how long before

The ISSN position stand gives 3–6 mg/kg of body mass.¹ As a calculation, for a 70 kg runner that range works out at 210–420 mg.¹ A 200 mg dose is about 2.9 mg/kg for the same runner, just under the low end of the range.¹ The IOC statement gives the same range.² The top of the range is not a target: start at the low end, and try it on a training run before you use more.

For timing, about 60 minutes before exercise is the most commonly used.¹ The IOC statement also places the dose about an hour before exercise.²

If you plan to use caffeine before running a race, use only a dose and timing you have already tried in training. The IOC statement says lower doses and different timings should be trialled in training before competition.² Keep the rest of race morning familiar too; see what to eat before a run for the food side, carb loading before a race for race-week fuelling, and how long a marathon taper should be for the week before.

Capsule, gum or coffee

Much of the research used anhydrous caffeine in a capsule, and the ISSN stand says caffeine chewing gum may need a shorter wait before exercise.¹ The running meta-analysis notes that different sources of caffeine, such as capsules, tablets, gums and drinks, may affect its pharmacokinetics, how the body absorbs and handles it.³

On coffee, the ISSN stand says it may improve lower-body muscular endurance about as well as isolated caffeine, in studies that were not specific to running.¹ Results differ between studies, likely because the dose of caffeine in coffee is hard to standardise.¹ For that reason, it says, most sport dietitians and nutritionists use anhydrous caffeine with their athletes.¹ No source here gives the caffeine in a cup of coffee, so this guide does not convert the dose into cups.

Side effects and who should take care

The ISSN stand lists tachycardia (a fast heart rate) and heart palpitations, anxiety and sleep disturbance among the most commonly reported side effects.¹ The IOC statement says doses of 9 mg/kg or more are more likely to raise the risk of nausea, anxiety, insomnia and restlessness.² The sources here give no heart-rate data from runners, only these reported effects.

What counts as too much caffeine before running? The ISSN stand says dose is the main factor in how often side effects happen and how severe they are.¹ Very high doses, such as 9 mg/kg, are linked to a high incidence of side effects.¹ The IOC statement says doses of 9 mg/kg or more do not appear to increase the performance benefit.²

People also respond differently. The ISSN stand says habitual caffeine intake may play a role in the differences between people, and calls for a case-by-case approach.¹ It also says caffeine may be broken down more slowly in pregnancy or with hormonal contraceptives.¹

The sources here give no list of who should avoid caffeine, and no daily limit. If you are pregnant, have a heart condition, take any medicines, or are under 18, ask a doctor or dietitian before using caffeine for running.

Where the evidence is thin or mixed

The time-trial results are the weakest part. The running meta-analysis found a small effect overall, and no significant benefit within trained or within recreational runners alone.³ Its authors say more evidence is needed for women; 19 of the 254 participants were women.³ The umbrella review says most studies were in young men.⁴

The best dose is not settled either. The running studies used 3–9 mg/kg, and the meta-analysis says the best dose to maximise the benefit has not been established.³ It rated the studies’ overall quality as unclear-to-low risk of bias.³ Responses also vary between people, and how much caffeine they usually have may play a part.¹

Finally, a lab test is not a race. The running meta-analysis calls time-to-exhaustion tests an unusual scenario compared with running in the real world.³ In practice, treat 3–6 mg/kg as a range to test from the low end, not a promise of a faster time.

Common questions

Is caffeine before running bad?

It depends mostly on the dose. The ISSN stand says dose is the main factor in side effects, and very high doses such as 9 mg/kg bring a high incidence of them.¹ Commonly reported effects include a fast heart rate, palpitations, anxiety and sleep disturbance.¹ If you have a medical condition or take medicines, ask a doctor or dietitian first.

How much caffeine before running?

The ISSN stand and the IOC statement both give 3–6 mg/kg of body mass.^{1, 2} For a 70 kg runner, that is 210–420 mg by calculation.¹ Start at the low end.

How long before a run should I take it?

About 60 minutes before exercise is the most commonly used timing.¹ The IOC statement also puts it about an hour before.²

Are caffeine pills better than coffee?

Not clearly. The ISSN stand says coffee may improve performance, but results differ between studies, likely because the dose of caffeine in coffee is hard to standardise; those studies were not specific to running.¹ So most sport dietitians and nutritionists use anhydrous caffeine with their athletes.¹ The running meta-analysis adds that different sources of caffeine may affect how the body handles it.³ No source here gives the caffeine in a cup, so whichever you use, try it on a training run first.

This guide is general information, not medical advice. If you have an injury, a health condition or are pregnant, ask a doctor or physiotherapist before changing how you train or eat.

Related guides

• What to eat before a run: timing, carbs and the researchThe ISSN position stand says carbohydrate-rich snacks or meals are commonly recommended in the hours before longer, harder exercise. For shorter exercise, a meta-analysis found no performance benefit from eating first.
• Carb loading before a marathon: what the research saysA 2026 meta-analysis suggests more than 8 g of carbohydrate per kg of body mass per day for 36–48 h before competition to raise muscle glycogen. Whether that improves race performance is not settled.
• How long should a marathon taper be?Two to three weeks, with weekly volume cut and fast running and most running days kept, is what the research supports. Whether two or three is better is not settled.

Sources

1. Guest NS, VanDusseldorp TA, Nelson MT, Grgic J, Schoenfeld BJ, Jenkins NDM, Arent SM, Antonio J, Stout JR, Trexler ET, Smith-Ryan AE, Goldstein ER, Kalman DS, Campbell BI. International society of sports nutrition position stand: caffeine and exercise performance. Journal of the International Society of Sports Nutrition. 2021. doi:10.1186/s12970-020-00383-4
2. Maughan RJ, Burke LM, Dvorak J, Larson-Meyer DE, Peeling P, Phillips SM, Rawson ES, Walsh NP, Garthe I, Geyer H, Meeusen R, van Loon LJC, Shirreffs SM, Spriet LL, Stuart M, Vernec A, Currell K, Ali VM, Budgett RG, Ljungqvist A, Mountjoy M, Pitsiladis YP, Soligard T, Erdener U, Engebretsen L. IOC consensus statement: dietary supplements and the high-performance athlete. British Journal of Sports Medicine. 2018. doi:10.1136/bjsports-2018-099027
3. Wang Z, Qiu B, Gao J, Del Coso J. Effects of caffeine intake on endurance running performance and time to exhaustion: a systematic review and meta-analysis. Nutrients. 2022. doi:10.3390/nu15010148
4. Grgic J, Grgic I, Pickering C, Schoenfeld BJ, Bishop DJ, Pedisic Z. Wake up and smell the coffee: caffeine supplementation and exercise performance: an umbrella review of 21 published meta-analyses. British Journal of Sports Medicine. 2020. doi:10.1136/bjsports-2018-100278