Multiple Models Can Concurrently Explain Fatigue During Human Performance

One of the most commonly and thoroughly studied paradigms of human performance is fatigue. However, despite volumes of research there remains considerable controversy among scientists regarding definitive conclusions about the specific mechanism(s) contributing to fatigue. Within the literature there are three primary yet distinctly different governing ideas of fatigue; the traditionally referenced central model and peripheral model as well as the emerging central governor model (CGM). The CGM has recently been advocated by a limited number of researchers and is suggestive of a more integrative model of fatigue when compared the traditional peripheral and central models. However, more work is needed to determine the specific and perhaps synergistic roles of each paradigm during exercise or sport activity. This article contains three components; (1) a brief overview of the problems associated with defining fatigue, (2) a description of the models governing interpretation of fatigue and, (3) a presentation of multiple interpretations of selected data to demonstrate that some results can be reasonably explained using multiple models of fatigue, often concurrently. The purposes of this paper are to reveal that a) perhaps it is not the results that suggest a certain paradigm of regulation, yet that it may be a product of an a priori definition that is being employed and b) an integrative model of central and peripheral fatigue may present a plausible explanation for fatigue vs. adherence to the notion that each paradigm is mutually exclusive.