This document discusses theories of arousal and its relationship to performance. It defines arousal and activation, and lists effects of arousal such as increased heart rate and sweating. It describes four theories of arousal: drive theory, inverted U theory, catastrophe theory, and the zone of optimal functioning. The inverted U theory proposes that performance increases with arousal up to an optimal point, after which further increases in arousal hurt performance. Being in the zone is described as a state of confidence, focus, control and flow. Strategies for achieving the zone include imagery and controlling anxiety levels.