Catching a wave really is a big thrill! Did you know that big-wave surfers get such an adrenalin rush that they maintain high, prolonged heart rates (90 percent of maximum based on treadmill tests) for periods greater than any other sports people. A rate of more than 180 beats per minute for three hours has been recorded in a professional big-wave surfer. Not surprisingly, surfers can be exhausted for a week after battling the waves. The psychological component of heart rate gets little a...