Evaluation's Options of Diurnal Variation of Physical Performance of University Students: A Pilot Study

IntroductionThe diurnal rhythms and their impact on sports performance during the day present the sphere of sports chronobiology which is examined in detail. The diurnal rhythms are the part of circadian rhythms. The circadian rhythms last according to many researches approximately 24 hours (Aschoff, 1990, 1995 and 1998, Arendt, 1998, Zeman, 2009) and are divided in two phases: the first phase (lasting from 3.00 AM to 3.00 PM) and the second phase (lasting from 3.00PM to 3.00 AM). Mentioned phases are characterized by variations of biochemical, physiological and psychological processes including exogenous sports performance. According to the mentioned variations we distinguish the human typology whose organism prefers one part of the day. The morning type of human-being (the morning chronotype) is a type who is more active mainly in the morning. The morning chronotype is able to show and perform maximal physical performance during these morning hours. This type is also known under the term "lark" because this type wakes up early in the morning and goes to bed early in the evening. The evening type of human, the evening chronotype, is more active in the second part of the day (in the afternoon or in the evening). The evening chronotype is known under the term "owl" which is characterized by getting up later in the morning and this human's type needs to go to bed in late evening hours or in hours after the midnight. Literature presents one more chronotype - neither type (intermediate, neutral), whose performance and the other characteristics are in balance and this type does not prefer any specific part of the day. Horne & Ostberg (1976), Reilly et al. (2007), Harada et al. (2011), Muro et al. (2011), Roenneberg (2012), Waterhouse, Fukuda & Morita (2012) etc. agree with mentioned chronotypesclassification. Horne & Ostberg (1976) presented the questionnaire thanks to which we can identify the chronotype to general population.Nowadays, there are available lots of results which are interested in the sphere of exogenous rhythms. Schlank & Pupis (2007) examined performances variations of speed- strength abilities during the day of the ski jumper. The authors denoted that the ski jumper achieved the highest performance at 12.00 (noon). Roskova & Demjan (2011) examined psychological and physical performance of female university students (n = 24) at 8.00 AM, 11.00 AM, 2.00 PM and at 5.00 PM. The maximal performance was achieved at 5.00 PM. Paugschova & Ondracek (2011) examined the diurnal rhythm of speed and strength abilities of female students attending secondary school (n = 10) at 9.00 AM, 12.00 (noon), 3.00 PM and at 6.00 PM. The strength predispositions showed maximal values at 9.00 AM and at 6.00 PM, and speed predispositions showed maximal values at 12.00 (noon). In the next researches authors presented the researches in which they examined the relationship between the chronotype and diurnal performance. Edwards et al. (2005), Kunorozva, Roden & Rae (2014) examined the impact of the chronotype on diurnal performance of professional cyclists. Authors denoted that the cyclists belonged to the morning chronotype according to the Horne & Ostberg' chronotype questionnaire and their performance was better in the morning when comparing with the evening performance. Very interesting results of cycliststesting were brought by Atkinson et al. (2005). Their research showed that the athletes belonged to the morning chronotypes but their sports performance was better not in the morning as they predicted but in the evening hours. Rae, Stephenson & Roden (2015) also examined the relationship between the chronotype (identified by chronotypes questionnaire) and sports performance. Results expressly showed that professional swimmers of the morning chronotypes achieved better results in morning trainings and professional swimmers of the evening and neither chronotypes achieved better performance and lower fatigue in the evening hours. …