Is recovery driven by central or peripheral factors? A role for the brain in recovery following intermittent-sprint exercise

Abstract

Prolonged intermittent-sprint exercise (i.e., team sports) induce disturbances in skeletal muscle structure and function that are associated with reduced contractile function, a cascade of inflammatory responses, perceptual soreness, and a delayed return to optimal physical performance. In this context, recovery from exercise-induced fatigue is traditionally treated from a peripheral viewpoint, with the regeneration of muscle physiology and other peripheral factors the target of recovery strategies. The direction of this research narrative on post-exercise recovery differs to the increasing emphasis on the complex interaction between both central and peripheral factors regulating exercise intensity during exercise performance. Given the role of the central nervous system (CNS) in motor-unit recruitment during exercise, it too may have an integral role in post-exercise recovery. Indeed, this hypothesis is indirectly supported by an apparent disconnect in time-course changes in physiological and biochemical markers resultant from exercise and the ensuing recovery of exercise performance. Equally, improvements in perceptual recovery, even withstanding the physiological state of recovery, may interact with both feed-forward/feed-back mechanisms to influence subsequent efforts. Considering the research interest afforded to recovery methodologies designed to hasten the return of homeostasis within the muscle, the limited focus on contributors to post-exercise recovery from CNS origins is somewhat surprising. Based on this context, the current review aims to outline the potential contributions of the brain to performance recovery after strenuous exercise.

Keywords: central nervous system; contractile function; fatigue; football; muscle damage; soccer; team-sports.

Figure 1

Time-course change in (A) maximal voluntary contraction of leg extensors, (B) voluntary activation of leg extensors, (C) creatine kinase, (D) C-reactive protein, and (E) perceived muscle soreness following prolonged intermittent-sprint exercise. These data are redrawn from the studies of Pointon and Duffield (2012), Pointon et al. (2012); Skein et al. (2013), Minett et al. (2013), and Murphy et al. (2013). A collated mean value derived from each of the aforementioned studies has been calculated and is also presented.