The inverted-U hypothesis is a classic model describing the relationship between arousal and performance. As arousal increases from a low level, performance improves — up to an optimal point. Beyond that peak, further increases in arousal cause performance to decline, producing a curve shaped like an upside-down U.
The practical implication is important: the goal is not to minimize arousal, but to reach an optimal level. Too little arousal leaves an athlete flat and under-activated; too much causes tension, rushed decisions, and attentional narrowing. The optimal point varies by athlete, by sport, and by task — an explosive event needs higher arousal than a precision task.
This model underpins the skill of arousal regulation: knowing your optimal zone and having tools to move toward it from either direction. A more individualized refinement of this idea is the zone of optimal functioning, which recognizes that each athlete has their own ideal arousal range.