Int J Sports Med 2017; 38(1): 41-47
DOI: 10.1055/s-0042-115033
Training & Testing
© Georg Thieme Verlag KG Stuttgart · New York

Electrostimulation Training Effects on diurnal Fluctuations of Neuromuscular Performance

H. Gueldich1, N. Zarrouk1, 2, H. Chtourou1, F. Zghal3, S. Sahli1, H. Rebai1
  • 1Research Unit: “Education, Motricity, Sports and Health” (UR 15JS01), Higher Institute of Sport and Physical Education of Sfax, University of Sfax, Sfax, Tunisia
  • 2Research Laboratory: “Medical Imaging Technologies” (LR 12ES06, TIM), Faculty of Medicine of Monastir, University of Monastir, Monastir, Tunisia
  • 3Laboratoire Adaptations Métabolique à l’Exercice en Conditions Physiologiques et Pathologiques (AME2P, EA 3533), Université Blaise Pascal, Clermont-Ferrand, France
Further Information

Publication History



accepted after revision 01 August 2016

Publication Date:
28 October 2016 (eFirst)

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.