How much caffeine should you take before training?

The ISSN position stand puts the ergogenic dose at 3-6 mg per kilo of body weight, taken 30-60 minutes before. For 70 kg that is 210-420 mg. Going higher gives no more performance and does give more jitters, a racing heart and worse sleep.

How much caffeine a day is safe?

EFSA considers up to 400 mg a day and 200 mg in a single serving safe for a healthy adult. Everything counts: coffee, tea, cola drinks, energy drinks and pre-workout. It is easy to overshoot when the pre-workout has 300 mg and you have also had two coffees.

Are caffeine capsules or coffee better?

For performance, what counts is the milligrams, and a capsule has the advantage that you know exactly how many: a coffee can range from 60 to 150 mg depending on the bean and the machine. If you like coffee and it agrees with you, it does the same job.

Do you lose the effect if you take it every day?

Tolerance reduces part of the effect, especially the subjective part. Saving it for demanding sessions, or cutting back for a few days before a competition, restores a good part of the response.

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Caffeine · Strong evidence

What caffeine is for and how much to take before training

The short answer. Caffeine is, alongside creatine, the supplement with the most performance evidence there is, and the only one on this site with an effect you notice on day one. It works by blocking adenosine receptors: it does not give energy, it delays the perception of fatigue. The effective dose goes by body weight (3-6 mg per kilo) and the safety limit for adults set by EFSA is 400 mg a day.

Several meta-analyses or position stands from scientific societies agree that there is an effect. No figure on this page is attributed to a specific product: the effect belongs to the ingredient and every number carries its source next to it.

01 What it does and how much

Each row is a measured effect, with the figure the study gives and the source number. Where the evidence gives no figure, the column says so instead of making up a percentage.

Effects of caffeine with their source
Effect	How much	Detail
Ergogenic dose	3 to 6 mg per kilo	For 70 kg, 210 to 420 mg. Above 9 mg/kg there is no more performance and there are more side effects. [1]
Endurance	where it works best	The effect is more consistent in endurance efforts than in maximal strength, although the position stand also reports improvements in strength and power. [1]
Perceived effort	lower	It is the most practical mechanism: the same set feels less hard. That is where the extra reps come from. [1]
Safe limit for adults	400 mg a day	And 200 mg in a single serving, according to EFSA’s assessment for healthy adults. Counting coffee, soft drinks and pre-workout together. [2]
Window of action	peaks at 30-60 min	And a half-life of 3 to 5 hours: a dose at seven in the evening is still in your body at midnight. [1]

02 How to take it

Dose. 3 to 6 mg per kilo of body weight, 30 to 60 minutes before.
When. Before training, and more than 6 hours before bedtime.
How long before you notice it. Acute effect, within the same session.

Details that change the result

Count everything you already take: a brewed coffee is 80-120 mg and a pre-workout 200-300. The 400 mg limit is for the whole day.
Tolerance rises with daily use. Cutting back for a few days before a competition restores part of the effect.
Caffeine capsules give an exact dose, which is their only real advantage over coffee.
It interferes with sleep long after you stop feeling it, and sleeping worse costs more performance than the capsule gives.

03 When it makes sense and when it does not

Worth it if

Demanding endurance sessions or hard training with low energy.
Competition, where the margin in perceived effort matters.
When you want an exact, repeatable dose, which coffee does not give.

Not worth it if

Late afternoon or evening if you train late: the cost of sleeping worse outweighs the benefit.
Stacking pre-workout, coffee and a soft drink without counting the milligrams.
With uncontrolled high blood pressure, arrhythmias, anxiety or pregnancy, where the limit is different and set by a doctor.

04 Sources

Every figure above comes from here. They are position stands from scientific societies, meta-analyses and peer-reviewed reviews: if a claim cannot hang from one of these lines, it is not on the page. References are cited in their original form.

Guest NS et al. ISSN position stand: caffeine and exercise performance. J Int Soc Sports Nutr. 2021;18:1. Dosis ergogenica de 3-6 mg/kg, 30-60 minutos antes; sin beneficio adicional por encima de 9 mg/kg. doi:10.1186/s12970-020-00383-4
EFSA Panel on Dietetic Products, Nutrition and Allergies. Scientific Opinion on the safety of caffeine. EFSA Journal. 2015;13(5):4102. Hasta 400 mg al dia y 200 mg en dosis unica no plantean problemas de seguridad en adultos sanos. doi:10.2903/j.efsa.2015.4102

This is not medical advice. It is what some studies say about an ingredient, not a protocol for you. With an illness, medication or pregnancy involved, the decision belongs to a healthcare professional who knows you.

Questions about caffeine

Answered with the data on this page

How much caffeine should you take before training?: The ISSN position stand puts the ergogenic dose at 3-6 mg per kilo of body weight, taken 30-60 minutes before. For 70 kg that is 210-420 mg. Going higher gives no more performance and does give more jitters, a racing heart and worse sleep.
How much caffeine a day is safe?: EFSA considers up to 400 mg a day and 200 mg in a single serving safe for a healthy adult. Everything counts: coffee, tea, cola drinks, energy drinks and pre-workout. It is easy to overshoot when the pre-workout has 300 mg and you have also had two coffees.
Are caffeine capsules or coffee better?: For performance, what counts is the milligrams, and a capsule has the advantage that you know exactly how many: a coffee can range from 60 to 150 mg depending on the bean and the machine. If you like coffee and it agrees with you, it does the same job.
Do you lose the effect if you take it every day?: Tolerance reduces part of the effect, especially the subjective part. Saving it for demanding sessions, or cutting back for a few days before a competition, restores a good part of the response.

And now, which to buy

Prices, kept apart from the evidence

This page explains what caffeine does and deliberately names no brand. The comparison is the other half: 86 products from 9 stores from €0.025 per capsule, sorted by price and by how verifiable their certification is.

See the caffeine comparison

Other guides

What each supplement does, with its sources