inverted U hypothesis

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An hypothesis applied to sport, which states that performance improves as arousal levels increase up to an optimum point, beyond which it deteriorates. In practice, this means that a little excitement and stress associated with competition or performing in public can have a positive effect, but a situation that is too stressful is detrimental. The optimal levels vary between people doing the same task and for the same person doing different tasks. Optimum arousal levels tend to be lower for more complicated tasks. See also catastrophe theory.

Hypothesis that states that performance improves with increasing levels of arousal up to an optimal point beyond which further increases in arousal produce a detrimental effect on performance. Therefore, athletes may perform badly because they are over- or under-aroused. The hypothesis is qualitative, and does not attempt to quantify the relationship between arousal and performance. The optima vary between people doing the same task and one person doing different tasks. A basic assumption in the hypothesis is that arousal is unidimensional and that there is, consequently, a very close correlation between indicators of arousal; this is not the case. See also catastrophe theory.

Inverted-U hypothesis