Caffeine later in the day before training: what it gives you and what it costs your sleep

General information, not medical advice. If you have sleep problems, are pregnant or take medication, discuss caffeine with your GP.

Caffeine later in the day, before a training session after work, can give your performance a small lift, but it is still active hours later when you want to sleep. It often comes from coffee or from a pre-exercise supplement, a powder or drink taken before training that usually contains caffeine.

What caffeine does for your training

The International Society of Sports Nutrition (ISSN), an association of sports nutrition researchers, reviewed the evidence (Guest and colleagues, 2021). In many studies, though not all, caffeine gave a small to moderate gain in muscle strength, muscular endurance, sprinting and jumping. Participants were usually given 3 to 6 milligrams per kilogram of body weight, mostly an hour before exercise. For someone weighing 70 kilograms, 3 milligrams per kilogram is about 210 milligrams, a dose used in research and not a recommendation.

An overview of 21 meta-analyses, studies that pool the results of many trials, found the effect is generally larger for endurance than for short, explosive efforts (Grgic and colleagues, 2020). The evidence was mostly of moderate quality and came mainly from young men. According to the European Food Safety Authority (EFSA), single doses of up to 200 milligrams raise no safety concerns for healthy adults, even shortly before intense exercise.

What caffeine later in the day costs your sleep

EFSA also notes that as little as 100 milligrams may affect sleep in some adults, particularly close to bedtime. A meta-analysis of 24 studies found that caffeine cut total sleep time by 45 minutes on average and deep sleep by 11.4 minutes (Gardiner and colleagues, 2023). To avoid losing sleep, the researchers calculated that a coffee (107 milligrams) should be had at least 8.8 hours before bedtime, and a standard portion of pre-exercise supplement (217.5 milligrams) at least 13.2 hours before. If you go to bed at 10.30 pm, that limit falls at around 9.15 am for such a portion. These are averages, not a strict rule.

In a smaller study, 12 healthy sleepers took 400 milligrams of caffeine 0, 3 or 6 hours before their usual bedtime (Drake and colleagues, 2013). Even when taken 6 hours before, it left them sleeping more than an hour less according to the monitor, while their sleep diaries showed a smaller, statistically uncertain loss of 41 minutes. So you can sleep worse without really noticing it.

In 15 trained male runners, 6 milligrams per kilogram taken at 7 pm did not lead to a faster 800 metres at 8 pm, but it did lower sleep efficiency, increase awakenings and leave them feeling less refreshed in the morning (Ramos-Campo and colleagues, 2019). This is one small study in young men, not proof that caffeine never helps in the evening.

Why not everyone is equally sensitive

The half-life is the time it takes your body to break down half of the caffeine. On average it is between 4 and 6 hours, but in adults it can range from 1.5 to 10 hours (Guest and colleagues, 2021). Pregnancy and the contraceptive pill slow the breakdown, smoking and heavy caffeine use speed it up, and your genes play a part too. In older adults, sleep may be more sensitive to caffeine than in younger adults (Clark and Landolt, 2017).

How much caffeine is in your cup or your powder?

EFSA uses about 80 milligrams for an espresso, 90 for a cup of filter coffee and 50 for a cup of black tea. In reality the amounts vary widely: for coffee and for pre-exercise supplements, eight- to ninefold differences have been measured (Guest and colleagues, 2021). The amount per portion is on the pack, and you can read what else to look for in how to read a supplement label. Over a whole day, EFSA sees no safety concern with up to 400 milligrams for healthy adults, and up to 200 milligrams during pregnancy.

Your options when you train in the evening

You can move the training session or the caffeine earlier in the day, take less caffeine or train without it. The Flemish health institute Gezond Leven advises no more than 4 cups of coffee or tea a day, and preferably no coffee or tea after 3 pm. If you find it hard to fall asleep after evening exercise, Gezond Leven suggests leaving at least two hours between exercise and sleep. Why your nights matter so much for recuperation is explained in the checklist on sleep and recuperation.

Sources

• EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA) (2015). Scientific Opinion on the safety of caffeine. EFSA Journal, 13(5), 4102.
• EFSA. Caffeine (topic page with the conclusions and indicative values). Accessed 17 October 2026.
• Guest NS, VanDusseldorp TA, Nelson MT et al. (2021). International society of sports nutrition position stand: caffeine and exercise performance. Journal of the International Society of Sports Nutrition, 18(1), 1.
• Grgic J, Grgic I, Pickering C, Schoenfeld BJ, Bishop DJ, Pedisic Z (2020). Wake up and smell the coffee: caffeine supplementation and exercise performance, an umbrella review of 21 published meta-analyses. British Journal of Sports Medicine, 54(11), 681–688.
• Gardiner C, Weakley J, Burke LM et al. (2023). The effect of caffeine on subsequent sleep: A systematic review and meta-analysis. Sleep Medicine Reviews, 69, 101764.
• Drake C, Roehrs T, Shambroom J, Roth T (2013). Caffeine effects on sleep taken 0, 3, or 6 hours before going to bed. Journal of Clinical Sleep Medicine, 9(11), 1195–1200.
• Ramos-Campo DJ, Pérez A, Ávila-Gandía V, Pérez-Piñero S, Rubio-Arias JÁ (2019). Impact of caffeine intake on 800-m running performance and sleep quality in trained runners. Nutrients, 11(9), 2040.
• Clark I, Landolt HP (2017). Coffee, caffeine, and sleep: A systematic review of epidemiological studies and randomized controlled trials. Sleep Medicine Reviews, 31, 70–78.
• Vlaams Instituut Gezond Leven (Flemish health institute). Je slaap verbeteren (in Dutch). Accessed 17 October 2026.