ABSTRACT
Circadian rhythms refer to cyclical changes occurring over the solar day. Human circadian rhythms influence many aspects of human performance (Waterhouse et al., 2002). In the main, changes in performance follow closely the circadian curve in body temperature with a peak at about 17:00 hours and a trough at 05:00 hours. Football games may take place at various times throughout the day whilst training may be held in the morning or afternoon. Whilst many physiological functions related to football, for example muscle strength and self-paced endurance performance, have been studied (Reilly et al., 1997), there has been no attention given to the study of time-of-day effects on game-related skills. The main purpose of the study was to analyse the effects of the time of day on specific performance tests in football players.
