title: Electrostimulation Training Effects on diurnal Fluctuations of Neuromuscular Performance.
abstract: This study examined the effects of electrostimulation (ES) strength training at the same time-of-day on the diurnal fluctuations of maximal voluntary isometric contractions (MVIC) and surface electromyography (EMG). 20 male performed 3 MVICs of knee extension coupled with surface EMG before and after 5 weeks of 3 ES training sessions per week. Each ES training session consisted in 45 isometric contractions. The participants were randomly assigned to either a morning (MTG, 07:00-08:00 h) or an evening (ETG, 17:00-18:00 h) training group. Both groups performed the evaluation tests at 07:00 and 17:00 h. Before ES training, MVIC was significantly higher in the evening compared to the morning for all groups, but there was no significant difference between groups for all EMG parameters. After the ES training, the diurnal variations in MVIC were blunted in the MTG and persisted in the ETG. Significant time-of-day effect was noticed for all EMG parameters but there was no group effect. The elimination of the diurnal fluctuations of MVIC and the appearance of EMG variations by training in the morning hours suggest that neural adaptations are the main source of temporal specificity of neuromuscular performance after ES strength training.
authors: Research Unit: "Education, Motricity, Sports and Health" (UR 15JS01), Higher Institute of Sport and Physical Education of Sfax, University of Sfax, Sfax, Tunisia.
authors: H
authors: H
authors: Gueldich
authors: Research Unit: "Education, Motricity, Sports and Health" (UR 15JS01), Higher Institute of Sport and Physical Education of Sfax, University of Sfax, Sfax, Tunisia.
authors: N
authors: N
authors: Zarrouk
authors: Research Unit: "Education, Motricity, Sports and Health" (UR 15JS01), Higher Institute of Sport and Physical Education of Sfax, University of Sfax, Sfax, Tunisia.
authors: H
authors: H
authors: Chtourou
authors: Laboratoire Adaptations Métabolique à l'Exercice en Conditions Physiologiques et Pathologiques (AME2P, EA 3533), Université Blaise Pascal, Clermont-Ferrand, France.
authors: F
authors: F
authors: Zghal
authors: Research Unit: "Education, Motricity, Sports and Health" (UR 15JS01), Higher Institute of Sport and Physical Education of Sfax, University of Sfax, Sfax, Tunisia.
authors: S
authors: S
authors: Sahli
authors: Research Unit: "Education, Motricity, Sports and Health" (UR 15JS01), Higher Institute of Sport and Physical Education of Sfax, University of Sfax, Sfax, Tunisia.
authors: H
authors: H
authors: Rebai
mesh_terms: D000222:Adaptation, Physiological; D002940:Circadian Rhythm; D004558:Electric Stimulation; D004576:Electromyography; D006801:Humans; D007537:Isometric Contraction; D007717:Knee; D008297:Male; D053580:Muscle Strength; D018482:Muscle, Skeletal / Q000502:physiology*; D055070:Resistance Training / Q000379:methods*; D055815:Young Adult