How Caffeine

Caffeine gives you a jolt of energy, but sometimes that jolt can mirror the symptoms of anxiety: jittery nervousness, heart palpitations, even feelings of panic. That's your "fight or flight" response taking over. The less you take in, the less you trigger that response and the anxiety that comes with it.

Some studies show that caffeine can help your body recover more quickly after hard exercise by making and restocking a stored form of fuel called glycogen. It seems to do this best if you combine it with carbohydrates, like in certain sports gels, sports bars, and drinks. Just take care not to overdo the caffeine, which could have the opposite effect on recovery or performance if it interferes with your sleep.

If you have caffeine every day, whether in a pill, energy bar, or cup of coffee, you build up tolerance. Then, without your daily dose, you might get a "rebound" headache. It may be worse if you quit caffeine completely and all at once. You'll find your head will feel better if you reduce caffeine a little at a time.