title: Circadian rhythm effect on physical tennis performance in trained male players.
abstract: To determine the effect of circadian rhythm on neuromuscular responses and kinematics related to physical tennis performance, after a standardised warm-up, 13 highly competitive male tennis players were tested twice for serve velocity/accuracy (SVA), countermovement vertical jump (CMJ), isometric handgrip strength (IS), agility T-test (AGIL) and a 10-m sprint (10-m RUN). In a randomised, counter-balance order, tennis players underwent the test battery twice, either in the morning (i.e., AM; 9:00 h) and in the afternoon (i.e., PM; 16:30 h). Paired t-tests were used to analyse differences due to time-of-day in performance variables. Comparison of morning versus afternoon testing revealed that SVA (168.5 ± 6.5 vs. 175.2 ± 6.1 km · h-1; P = 0.003; effect size [ES] = 1.07), CMJ (32.2 ± 0.9 vs. 33.7 ± 1.1 cm; P = 0.018; ES = 1.46), AGIL (10.14 ± 0.1 vs. 9.91 ± 0.2 s; P = 0.007; ES = 1.23) and 10-m RUN time (1.74 ± 0.1 vs. 1.69 ± 0.1 s; P = 0.021; ES = 0.67) were significantly blunted during the morning testing. However, IS was not affected by time-of-day (P = 0.891). Thus, tennis performance may be reduced when competing in the morning in comparison to early evening. Therefore, coaches and tennis players should focus on schedule the SVA, power, speed and agility training sessions in the afternoon.
authors.affiliation: a Exercise Physiology Laboratory , University of Castilla-La Mancha , Toledo , Spain.|b Faculty of Sports Sciences , European University of Atlantic , Santander , Spain.
authors.forename: Álvaro
authors.initials: Á
authors.lastname: López-Samanes
authors.affiliation: c Faculty of Sports Sciences , European University , Madrid , Spain.
authors.forename: Diego
authors.initials: D
authors.lastname: Moreno-Pérez
authors.affiliation: d Department of Physical Activity and Sport Sciences , Alfonso X El Sabio University , Madrid , Spain.
authors.forename: José L
authors.initials: JL
authors.lastname: Maté-Muñoz
authors.affiliation: d Department of Physical Activity and Sport Sciences , Alfonso X El Sabio University , Madrid , Spain.
authors.forename: Raúl
authors.initials: R
authors.lastname: Domínguez
authors.affiliation: a Exercise Physiology Laboratory , University of Castilla-La Mancha , Toledo , Spain.|e Faculty of Sports Sciences , University of Murcia , Murcia , Spain.
authors.forename: Jesús G
authors.initials: JG
authors.lastname: Pallarés
authors.affiliation: a Exercise Physiology Laboratory , University of Castilla-La Mancha , Toledo , Spain.
authors.forename: Ricardo
authors.initials: R
authors.lastname: Mora-Rodriguez
authors.affiliation: a Exercise Physiology Laboratory , University of Castilla-La Mancha , Toledo , Spain.
authors.forename: Juan F
authors.initials: JF
authors.lastname: Ortega
mesh_terms: D000328:Adult; D054874:Athletic Performance / Q000502:physiology*; D001696:Biomechanical Phenomena; D002940:Circadian Rhythm / Q000502:physiology*; D005080:Exercise Test / Q000379:methods; D006801:Humans; D007537:Isometric Contraction; D008297:Male; D064797:Physical Conditioning, Human; D059385:Plyometric Exercise; D013696:Temperature; D013715:Tennis / Q000502:physiology*; D013997:Time Factors
keywords: Time-of-day; agility test; counter movement jump; running sprint; tennis serve velocity