Sport And Exercise Psychology: A Critical Introduction

Part one suggests that people’s performance on skilled tasks is best when their level of
arousal is intermediate and that it deteriorates as their arousal either increases or
decreases from that optimal level In other words, the relationship between arousal and
performance looks like an inverted “U”. For example, as when you are either drowsy
(under-aroused) or very excited (over-aroused), it is difficult to do an exam to the best of
your ability. Part two of the Yerkes-Dodson law suggests that as the complexity of a skill
increases, the amount of arousal required for optimal performance of it decreases. In
other words, the performance of difficult tasks decreases as arousal increases whereas the
performance of easy tasks increases as arousal increases. In summary, the Yerkes-
Dodson law suggests that optimal performance occurs when people’s arousal levels are
intermediate in strength. Further details of this law may be found in Teigen (1994),

If the Yerkes-Dodson theory is correct, then athletic performance that occurs under
conditions of either high or low arousal should be inferior to that displayed at
intermediate levels. This hypothesis has received some empirical support. For example,
Klavora (1978) found that within a sample of high-school basketball players, the highest
levels of performance were displayed by people who had reported moderate levels of
somatic anxiety. More generally, Landers and Boutcher (1998) concluded that “the
inverted-U hypothesis seems to generalise across field and experimental situations” (p.
205).
Unfortunately, despite its plausibility, the Yerkes-Dodson principle is difficult to test
empirically for several reasons. First, as we learned earlier, it is not easy to devise or
agree on a satisfactory independent measure of the construct of arousal. As a result,
researchers find it difficult to decide whether a given arousal level is too low or too high
for a performer. Second, there is an inherent flaw at the heart of this law. In particular, as
researchers cannot predict in advance the point of diminishing returns for the effects of
arousal on skilled performance, the inverted-U hypothesis is “immune to falsification”
(Neiss, 1988, p. 353). Finally, researchers disagree about the best way in which to induce
different levels of arousal in participants. For ethical reasons, contemporary investigators
cannot use electric shocks or other forms of aversive stimuli for this purpose—unlike
their predecessors Yerkes and Dodson (1908). In summary, the inverted-U theory has
several flaws as a possible explanation of the link between arousal and performance.
Perhaps most significantly, it does not elucidate putative theoretical mechanisms which
might account for the link between arousal and performance. Thus the inverted-U is “a
general prediction, not a theory that explains how, why, or precisely when arousal affects
performance” (Gould et al, 2002, p. 214). Unfortunately, despite these limitations, this
hypothesis has been promulgated as an established fact by some applied sport
psychologists. To illustrate, Winter and Martin (1991) used it to justify their advice to
tennis players on “controlling ‘psych’ levels” (p. 17).

Catastrophe theory

The catastrophe theory of anxiety (e.g., Hardy, 1990; 1996; Hardy and Parfitt, 1991) is
different from the two previous arousal-performance models in proposing that
physiological arousal interacts with certain aspects of anxiety (in this case, cognitive

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