Personality-trait-like individual differences: much more than noise in the background for sport and exercise psychology

The aim of this chapter is to argue the case that personality-trait-like individual differences (PTLID) should be considered more than simple error variance by sport and exercise psychologists. PTLID carry their own valuable source of information, and provide added value to our field at the theoretical, methodological, and applied levels. At the theoretical level, PTLID should be incorporated into experimental studies to further test and constrain theoretical predictions. Here, we illustrate how current PTLID theories can inform psychological phenomena in the sport and exercise domain. In particular we elaborate on the example of the Take-the-First heuristic, to illustrate how conceptual models can be expanded using PTLID theories. At the methodological level, PTLID provide an important methodological control for potential confounding factors that might otherwise contribute to a false acceptance or rejection of theoretical predictions. At the applied level, understanding PTLID outcomes can assist psychologists in designing more targeted interventions that better fit the needs of the individual client. Moreover, that some PTLID can be trained is a particularly appealing notion for the developing athlete or beginner exerciser.