Bill Russell may be the most successful athlete in NBA history, but in all 13 of his seasons he got so nervous before games that he usually threw up. Everyone, no matter how well prepared, feels butterflies in stressful situations. Your heart rate increases, your breathing speeds up, and you start worrying about the likelihood of failure rather than focusing on the possibility of success. Your brain instantly tells your body to shut down amid the onslaught of adrenaline and cortisol. But have you ever considered doing the opposite? Like Russell, you can learn to exploit those chemicals rather than suppress them.