Health
Too much caffeine with strength training: when does the boost become a drawback?
Draft: this article is still being reviewed by a healthcare professional.
Short answer
Caffeine can support sports performance, but higher intakes do not automatically give better results. Restlessness, palpitations and poorer sleep can outweigh the benefit. [2]
Add up all sources
For healthy adults, EFSA generally sees no safety concern with single doses of up to 200 mg and up to 400 mg spread over a day. These are not target doses and no guarantee that you will stay free of symptoms. The assessment does not simply apply in case of illness or medication use. During pregnancy, a lower daily limit of 200 mg from all sources combined applies. [1]
A worked example: 200 mg from a pre-workout plus two drinks with 100 mg each adds up to 400 mg. Actual amounts differ per product and per cup of coffee, so check the servings.
Sleep counts too
Even 100 mg shortly before bed can affect sleep in some people. [1] If you can only manage evening training with more and more caffeine, also look at your planning and recovery.
When should you seek help?
Take symptoms seriously and do not take another dose to suppress fatigue. Chest pain, fainting or severe persistent palpitations need immediate medical assessment; if life is in danger, call 112. Do not use pure caffeine powder as a DIY pre-workout.
