title: Diurnal evolution of cycling biomechanical parameters during a 60-s Wingate test.
abstract: The purpose of this study was to assess the evolution of pedaling kinetics and kinematics during a short-term fatigue cycling exercise at two times of day. Twenty active male subjects were asked to perform a 60-s Wingate test against a constant braking resistance during two experimental sessions at 06:00 and 18:00 hours, i.e., very close to the hours of core temperature values, which are, respectively, the lowest and the highest. The results showed that the fatigue index was higher (P<0.05) at 18:00 hours (71.4%) than at 06:00 hours (69.2%) and power output was higher (P<0.05) in the evening than in the morning during the first 20 s of the test, after which no difference was observed. Taken together, these results showed a greater progression of fatigue in the evening than in the morning. The diurnal variations in performance and fatigue were associated (P<0.001) with diurnal changes in cycling kinematic parameters, characterized by a reduction in the range of motion of the ankle angle in the evening. These findings show that a time-of-day effect on movement patterns occurs during an anaerobic cycling exercise and that this phenomenon has a direct influence on performance and fatigue.
authors.affiliation: INSERM, ERI27, Caen, France.
authors.forename: R
authors.initials: R
authors.lastname: Lericollais
authors.forename: A
authors.initials: A
authors.lastname: Gauthier
authors.forename: N
authors.initials: N
authors.lastname: Bessot
authors.forename: D
authors.initials: D
authors.lastname: Davenne
mesh_terms: D001696:Biomechanical Phenomena / Q000502:physiology; D001831:Body Temperature; D002940:Circadian Rhythm / Q000502:physiology*; D005080:Exercise Test; D006801:Humans; D008297:Male; D018763:Muscle Fatigue / Q000502:physiology; D055815:Young Adult