Diurnal variations on cognitive performances in handball goalkeepers

Abstract

The purpose of this study was to examine the effects of the time of day on the cognitive performances of the handball’s goalkeeper (GK) in terms of attention and reaction time (RT). The protocol involved 12 healthy GK volunteer males (age: 18.5 ± 1.7 years, level of experience: 8.3 ± 2.4 years, height: 1.80 ± 5.8 cm, weight: 79 ± 4.2 kg). They performed three cognitive tasks, i.e. the RT test, the Stroop test, and the barrage test at 08:00, 12:00, 16:00, 20:00 h, and midnight to evaluate simple RT, and selective (SA) and constant (CA) attention. Resting oral temperature was measured at the beginning of each test session. The results showed a significant time-of-day effect on RT, SA, and CA. Whereas, RT was higher (slower) at midnight, SA and CA were the highest (best) at 08:00 h. Likewise, the core temperature was time-of-day dependent with the highest values observed at 16:00 h. Therefore, cognitive performances of GK are time-of-day-dependent with the highest values observed in the morning for SA and CA, and at midnight for RT. However, these rhythmicities are not in phase with the rhythm of core temperature. Therefore, the activities that require better cognitive performance should be programed in the morning.

Keywords:

• time-of-day
• circadian rhythm
• reaction time
• attention
• handball’s goalkeeper
• cognitive performances