If you’re feeling low on energy, caffeine might help you power through your workout.
Scientists think that caffeine, in addition to making you alert, may help preserve the glycogen (stored carbs) in your muscles. This mechanism may help workouts feel easier and more efficient.
There’s a caveat though: most of the benefits have been observed in elite athletes, not average folks who exercise casually.
Of course, if you’re sluggish before a workout, caffeine is a relatively safe way to perk up. Here are some guidelines:
Low doses are all you need. The scientific measurement is 3mg caffeine per kg of body weight. But for simplicity, start with one standard cup of coffee or tea.
Choose brewed coffee or tea instead of bottled energy drinks or supplements, which might have other unwanted ingredients.
Consume it ~45 minutes before a workout. The levels peak in your bloodstream after 60-100 minutes.
If you don’t normally drink coffee or caffeine, or if you’re sensitive to it, proceed with caution. You might be more likely to feel negative effects like jitters and a racing heart.
Avoid caffeine in the afternoon, as it can interfere with your sleep. A good rule of thumb is no caffeine after 2pm, however the exact cutoff time may be different for you.