Duration and Quality of Sleep in Sprint and Recovery Performances Among Elite Swimmers

Abstract

Introduction: Circadian rhythms can impact athletes' sports performance, where the plateau occurs between 15 and 21 hours. Swimming is a peculiar case, as athletes perform training and final sessions in competitions at different times, as in the Rio2016 Olympic Games for example, where the semifinal and final competitions took place from ten o'clock at night. Objectives: (1) to present the protocol of an intervention performed with elite athletes of the Brazilian swimming team during the 2016 Olympic Games in Rio; (2) to find out whether the time at which the competitions were held affected the swimming performances of these athletes during the competition. Materials and Methods: Fourteen athletes of the Brazilian swimming team (males: n= 10; 71% and females: n= 4; 29%) participated in the study. They were followed up during two preparation periods (baseline and intervention) for the 2016 Olympic Games in Rio during June and July 2016. During the competition, we recorded the Reaction Time (RT) and Competition Time (CT) of each athlete in different modalities. The intervention strategies used were light therapy and sleep hygiene. The values of RT at the starting block and CT were registered and conferred with the official results. Results: The athletes showed a decrease in the total time awake (Δ = −13%; Effect size [ES] = 1.0) and sleep latency (Δ = −33%; ES = 0.7), and an increase in total sleep time (Δ = 13%; ES = 1.1; p = 0.04) between the baseline and the period of the intervention, pre-competition. We identified an improvement in the RT (Δ = −2.2% to −1.0%; ES = 0.2 to 0.5) during the competition only for the athletes who participated in the competition finals. Conclusion: We conclude that the intervention carried out was effective in mitigating any negative influence of competition time on the RT and CT of elite athletes of the Brazilian swimming team. Level of evidence II; Prospective comparative study.

Was Postponing the Tokyo 2020 Olympic and Paralympic Games a Correct Decision?

“…In a study reporting athletes that participated in the Paralympic Games Beijing 2008, it was observed that 83.3% of athletes presented daytime sleepiness and also had poor sleep quality, and 72% presented medium anxiety levels, which also had a negative impact on the sleep quality 43 . Other studies 41,43,44,46 reported that Olympic athletes present poor sleep quality and low sleep efficiency, besides increased awakenings, fragmentation, and sleep latency, thereby reducing the physical and cognitive performance, as well as increasing the number of musculoskeletal injuries. The pressure to achieve better results, anxiety levels, and transmeridian 65 travels could affect the sleep quality and performance in athletes during sports 66 .…”

“…Olympic and Paralympic athletes often present bad sleep quality, sleep complaints, sleep disturbances, and inadequate sleep duration [39][40][41] , particularly during periods that precede important competitions [42][43][44][45] . Besides negatively affecting the sports performance 46 , sleep restriction presumably triggers important immunological alterations 37,47 . It has been observed that increased training load in combination with psychological pressure could lead to injuries 49 and sport diseases that compromise athletes' health 50 , being even more severe in the Paralympic athletes [51][52][53] .…”

The Sleep Parameters of Olympic Athletes: Characteristics and Assessment Instruments

“…Regarding subjective parameters, two studies [17,25] demonstrated that the most predominant chronotype is the indifferent one (78% and 64%, respectively), while one study [18] presented a 22% prevalence of daytime sleepiness. Subjective poor sleep quality was 49% in one of the studies [18] and 53% in the other study [19], demonstrating that from a combined sample of 263…”

“…Regarding objective methods to assess sleep, actigraphy was the most used instrument (n = 8) [12,17,21,22,[24][25][26], followed by polysomnography (n = 1) [16]. Regarding subjective methods to assess sleep, two studies used the PSQI [18,19], two studies used the sleep diary [21,24] and one study used the Likert scale to assess sleep quality [21].…”

“…Unauthorized distribution is strictly prohibited. [25]. Therefore, the sports calendar and competition schedules must be considered when planning the team.…”