Caffeine genuinely improves endurance, strength and focus in training, which is why it's in almost every pre-workout. The trick is dose and timing.
How much helps
Sports-nutrition research points to roughly 3–6 mg per kg of body weight for a performance benefit, about 200–400 mg for a 70 kg person. More than that rarely helps and just adds jitters. A strong coffee, around 150–200 mg, is enough for most people.
When to take it
Caffeine peaks in your blood 30–60 minutes after you drink it, so take it about 45 minutes before you train. That's also why a pre-workout is often one of your biggest caffeine hits of the day.
- Mind the timing. An evening workout means an evening dose, which can wreck your sleep.
- Caffeine-free pre-workout is a valid option for late training.
- It still counts toward your daily 400 mg limit.
A pre-workout is often someone's single biggest dose of the day. Caffy logs it in a tap and folds it into your daily total and your sleep cutoff, so training hard doesn't have to mean sleeping badly.