Chronotype, Physical Activity, and Sport Performance: A Systematic Review

Background Many variables related to sport have been shown to have circadian rhythms. Chronotype is the expression of circadian rhythmicity in an individual, and three categories of chronotype are defined: morning types (M-types), evening types (E-types), and neither types (N-types). M-types show earlier peaks of several psychophysiological variables during the day than E-types. The effect of chronotype on athletic performance has not been extensively investigated. Objective The objective of the present review was to study the effect of chronotype on athletic performance and the psychophysiological responses to physical activity. Methods The present review adheres to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) reporting guidelines. We searched PubMed, Scopus, and Web of Science for scientific papers using the keywords chronotype'', circadian typology'', `` morningness'', and eveningness'' in combination with each of the words sport'', performance'', and athletic.'' Relevant reference lists were inspected. We limited the search results to peer-reviewed papers published in English from 1985 to 2015. Results Ten papers met our inclusion criteria. Rating of perceived exertion and fatigue scores in relation to athletic performances are influenced by chronotype: M-types perceived less effort when performing a submaximal physical task in the morning than did N-and E-types. In addition, M-types generally showed better athletic performances, as measured by race times, in the morning than did N-and E-types. Other results concerning chronotype effect on physiological responses to physical activity were not always consistent: heterogeneous samples and different kinds of physical activity could partially explain these discrepancies. Conclusions Sports trainers and coaches should take into account the influence of both the time of day and chronotype effect when scheduling training sessions into specific time periods.