Effects of Sleep Loss on Sports Competition Performance

The Cause and Effects of Precompetition Sleep Loss on the Performance of Varsity Athletes

According to Zielinski, Mckenna and McCarley (2016), sleep is a crucial condition of the body that is critical for a variety of human processes and functions including energy conservation, cognition, and performance. Because of this, many often assume that the success of athletic performance is determined by the hours of sleep one receives. While there are copious studies that demonstrate how chronic sleep deprivation is detrimental to an athlete’s ability to perform, studies on short-term sleep loss are limited. This is problematic since numerous athletes reported having poorer sleep the night before a competition (Watson, 2017). Ultimately, this leads to the question of what factors affect an athlete’s ability to sleep the night before a competition and does precompetition sleep loss have an affect on their performance the next day. Due to the high prevalence of precompetition sleep loss amongst athletes, this topic is worth looking into. This study will discuss the behavioural causes of precompetition sleep loss on varsity athletes based on the type of sport they are in (team or independent), as well as their gender. It will also explore the biophysical effects that acute sleep loss may have on an athlete’s body and their ability to perform based on the intensity of the sport they play (aerobic or anaerobic). The aim of this study is to understand how precompetition sleep loss is experienced amongst different athletes and how it affects their athletic performance. Acquiring this information will further advance the knowledge of sleep behaviour in varsity athletes and will allow coaches and athletes to determine whether or not their performance is affected by a single night of reduced sleep.

Literature Review:

Factors contributing to precompetition sleep loss

In a study based on sleep and athletic performance, Watson (2017) recommends that adults should sleep 8 hours a night and explains that sleep not only has significant impacts on essential body functions, but it also plays a crucial role in reducing injuries and illnesses in athletes. Thus, sleep not only optimizes health, but it also improves performance through increased ability to participate in practices and training. Inspite of all these benefits, many varsity athletes still sleep below the recommended hours due to psychological and external stressors before a game/competition. One of the most common psychological stressors indicated among athletes is pre-game anxiety or nervous thoughts before a game (Lastella, Lovell and Sargent, 2012). Other factors such as jet lag, an unfamiliar environment, noise, early games/practices, awakenings and frequent trips to the bathroom also contributed to an athlete’s disturbed sleep the night prior to a competition (Lastella, Lovell and Sargent, 2012). However, these factors affect athletes differently depending on what type of sport they play (team or individual) and their gender. Based on previous studies, Erlacher et al. (2011) hypothesized that players of individual sports would experience more sleep difficulty than those who participated in team sports. This is because athletes who are a part of a team have a supportive group of teammates who share the pressure and psychological feelings of nervousness or anxiety. In contrast, athletes in individual sports experience more anxiety since all the pressure of the game falls onto them and they have only themselves to blame for the outcome of the competition. Also, because team sports generally play more games on a week to week basis, they have the opportunity to develop better sleep routines before a competition in comparison to individual athletes who compete on an irregular basis. Thus, because athletes involved in a team sport are exposed to more games, they may be immune to pregame anxiety or have developed coping mechanisms to help them overcome it. Additionally, Erlacher et al. (2011) also hypothesized that females would experience more sleep abnormalities since previous research displayed a higher insomnia rate in women than in men. Therefore, coaches should pay special attention to female athletes and individual athletes since they are most susceptible to precompetition sleep loss. Furthermore, alongside pregame nervousness, Watson (2017) illustrates that youth and collegiate athletes may experience additional stresses that threaten their sleep quality and duration. Since these athletes are still in school, academic pressure and stressors contribute significantly to their sleep loss. Oftentimes for student-athletes, sleep is sacrificed in order to make time for both academics and athletics. This not only compromises their health but may also negatively affect their academic and athletic performance.

Effects of sleep loss on performance

While the effects of sleep deprivation is known to be associated with a decrease in athletic performance, little is known about the effects of short-term precompetition sleep loss on an athlete’s ability to perform. In Erlacher et al.’s (2011) study, they indicate that reduced sleep causes harmful biophysical effects on the brain involving focus such as cognitive slowing and an inability to concentrate on a task over time. Thus, prolonged sports requiring quick decision making or accuracy would be negatively affected by acute sleep restriction. This is proven by Watson (2017) who conducted a study involving dart players where the accuracy decreased significantly after a single night of 4-5 hours of sleep. Additionally, in Azboy and Kaygisiz’s (2009) study, they found that one night of sleep loss caused a decreased time to exhaustion in progressive testing for volleyball players. Moreover, in Lastella, Lovell and Sargent’s (2012) study, they explored how one night of sleep deprivation would affect endurance. They discovered that after 30 minutes of running on a treadmill, the participants ran 187 metres less than when they were fully rested. Due to the athlete’s sleep loss, their accuracy, ability to focus and endurance deteriorated, proving that even small amounts of sleep loss can have harmful effects on performance. On the contrary, some studies reported no overall changes in performance after a single night of sleep loss. In Erlacher et al.’s (2011) study, 46.6% of the participants who had experienced precompetition sleep loss reported that it had no influence on their performance whereas only 14% of the participants who experienced precompetition sleep loss believed it hindered their ability to perform. Furthermore, in Takeuchi et al.’s (1985) study, they discovered no changes in a 40-m sprint performance after 64 hours of complete sleep deprivation. In Watson’s (2017) study, he measured the performance of collegiate weightlifters after one night of deprived sleep. He also found no significant changes in their ability to perform after one single night of disturbed sleep. These findings are contradictory to the previous ones since some athletes experienced no significant changes in their performance whereas others experience negative effects. However, from the studies, it seems that reduced sleep has a negative impact on activities that involve accuracy such as darts and aerobic activities that require endurance such as volleyball and long distance running. Shorter, high-intensity, anaerobic activities such as sprinting and weightlifting were not affected as much. Thus, it can be said that short-term sleep restriction has a negative effect on aerobic athletes since they require endurance and accuracy whereas anaerobic athletes are not affected since they involve shorter activities with high-intensity movements. Additionally, the results of the studies may also be affected by the time of day in which the athletes performed these activities. Thun et al. (2015) found that performance peaked during the evening for those involved in anaerobic activities such as weightlifting whereas performance was best during the morning for aerobic activities such as cycling. Performance normally would peak during the evening because that is when our body’s internal temperature is the greatest. However, for aerobic activities, fatigue and tired muscles are more prominent and thus leads to a decreased time to exhaustion. Moreover, some athletes may not be affected as much by short-term sleep restriction because humans are able to cope with the physiological and psychological stresses in the absence of sleep (Watson, 2017). Success can still be achieved even if athletes lack sleep depending on their ability to cope. Thus, some athletes who have been competing or playing the sport for a long time may have developed coping mechanisms to fight off the stressors associated with sleep loss so that their performance is not as easily effected.

The purpose of this study is to examine the causes of precompetition sleep loss among different athletes and the effects it has on their performance. The literature examined claims that female and independent athletes would be more susceptible to precompetition sleep loss due to psychological factors such as anxiety and stress. Additionally, the literature reviewed also suggests that negative biophysical factors affecting athletic performance are strongly associated with aerobic athletes rather than anaerobic athletes. The present paper will explore these theories and test whether or not they are true.

Methods:

Participants

Based on the information gathered from the literature review, precompetition sleep loss had different effects based on three factors, the type of sport (team or independent), gender, and the intensity of the sport (aerobic or anaerobic). For this study, aerobic activities involved light to moderate intensity movement for a longer period of time whereas anaerobic activities involved high-intensity movement for a shorter period of time. The four participants included in this study were all first year varsity athletes studying kinesiology from the University of Toronto who played different types of sports at different intensities. The first two participants consisted of one female from the track and field team and one male from the figure skating team. Both participants were independent athletes who participated in anaerobic activities. The other two participants consisted of one male from the basketball team and one female from the water polo team. Both participants were apart of team sports involving aerobic movement.

Process

Conducting interviews was the best method to explore whether or not precompetition sleep loss had an effect on athletic performance because it allowed for more in-depth experiences to be gathered from sport-specific people rather than having generalized information from a group of random athletes. Gathering detailed experiences from sport-specific athletes was essential for this study since the effect of precompetition sleep loss varied for everyone. During the interview, a variety of questions were asked to assess the theories mentioned in the literature review. This included questions that involved their sleeping patterns, performance, preferences of game times and experience with the sport.

Sleeping Patterns assessed whether the athlete experienced precompetition sleep loss by comparing the regular hours of sleep they receive to the amount of sleep they get the night before a competition. Also, how they felt before a game, how they were doing in school, how they adjusted to new environments and how they felt about the game/practice times were examples of questions that were asked to determine what factors contributed to their sleep loss.

Performance was evaluated based on the athlete’s own self assessment. How they felt throughout the competition after one night of sleep loss was compared how they felt on days where they were fully rested to assess whether precompetition sleep loss had an effect on their ability to perform.

Preferences of Game Time were important to determine whether Thun et al.’s theory discussed in the literature review was true. Questions such as when do you usually have your games, when do you prefer to have your games and when do you think your performance is at its peak were asked to not only test the theory but to also assess whether game time had an affect on their performance.

Experience with the Sport was asked to determine whether the athlete had the ability to cope with the psychological and physiological stressors associated with reduced sleep. How long have you played this sport is an example of the questions asked. This gives insight as to why some athletes may or may not experience precompetition sleep loss or why acute sleep loss may or may not have an impact on their performance.

Peer Review

Through the peer review process, the individual who looked over my paper found that I had over explained each interview in the data analysis portion and was being too repetitive. Instead of explaining each response, he suggested to include a generalized summary and discuss the patterns present amongst the four interviews instead of explaining each one in depth. After reviewing the data analysis section myself, I agreed with his critique and summarized my findings into one cohesive paragraph that highlighted the key trends and patterns. Additionally, the peer reviewer also found that my topic of inquiry was unclear since it was only stated once in the introduction. Thus, I added in a section at the end of my literature review that restated my topic of inquiry with reference to the information I found in the literature review.

Data Analysis

Trends/Patterns

Through conducting the interviews, the results illustrate how precompetition sleep loss is experienced by different athletes and how it affects their performance. The findings also proved and debunked the theories presented in the literature review.

Overall, all the athletes reported to experience precompetition sleep loss. Factors including school, anxiety, early games/competitions and adjusting to a new environment all contributed to their inability to sleep the night prior to competitions. Because all of these athletes are full time university students, their sleep is often compromised to make time for both academics and athletics. They reported to stay up late studying or finishing an assignment which resulted in reduced sleep. Moreover, three of the four athletes interviewed complained that early game/competition times also contributed to their lack of sleep. In one instance, the water polo player would often have late practices and early leave times in the morning for a competition. This not only minimizes her hours of sleep but also reduces the time she has to complete other tasks such as school work. Another contributing factor to reduced sleep was the initial adjustment to a new environment. Three of the four athletes reported having difficulty sleeping when they first moved to Toronto or when they travelled to a different city for competitions. Additionally, the behavioural sleep habits were also explored between team and independent athletes as well as male and female athletes. The theory that individual sport athletes would experience higher levels of anxiety compared to team sport athletes remained equivocal since all athletes from both team and individual sports reported feelings of anxiety and nervousness prior to games/competitions. The most common reason for feelings anxious before a game was the psychological fear of making mistakes. Furthermore, the theory that female athletes would experience more sleep abnormalities was proven to be inaccurate since the females in this study actually slept equal to or more than the male athletes. Also, the female athlete’s ability to sleep in the presence of nerves and anxiety were also better compared to the male athletes. Both female athletes reported that although they did feel anxiety before games, they felt it had no affect on their ability to sleep. On the contrary, the males found it difficult to fall asleep due to nervous thoughts about the game.

In terms of performance, the anaerobic athletes experienced no significant changes while the aerobic athletes reported to feel negative biophysical effects that reduced their ability to perform. From the interviews, the figure skater and sprinter did not experience significant changes to their performance after one night of poor sleep other than daytime fatigue and sore muscles. The figure skater’s ability to execute jumps was only affected on the second day of competitions where he would be significantly more sleep deprived because he would have an accumulation of loss sleep due to nervous thoughts that persisted over the two day competition. However his performance was generally unaffected on the first day of the competition even though he also experienced sleep loss the night before. On the contrary, the basketball and water polo athletes experienced biophysical detriments from the loss sleep that affected their performance. The basketball player felt he had a decreased time to exhaustion that limited his ability to play offence and defence maximally while the water polo player felt a decrease in alertness and accuracy. Due to the basketball player’s fourteen years of experience, endurance was the only factor that was negatively influenced from his lack of sleep. His focus, decision making and accuracy were not affected. On the contrary, since the water polo player only had four years of experience, factors such as her accuracy and reaction time were negatively affected by her lack of sleep. Thus, this proves that aerobic athletes are more affected by sleep loss than anaerobic athletes and proves that experience does play a role in performance. In terms of peak performance times, Thun et al.’s theory was proven correct since the anaerobic athletes seemed to prefer evening games/competitions while the aerobic athletes preferred morning games. Thus, in the case for aerobic athletes, even in the absence of sleep, if they were able to compete during their preferred times, their performance may not be affected as much.

Conclusion

This study explored the prevalence of precompetition sleep loss in varsity athletes and its effect on their performance. Overall, all athletes in the study exhibited precompetition anxiety, however only two of the four reported that it affected their sleep. Other factors such as school, early games/practice times and travelling however, also contributed to their inability to sleep the night before a competition. Contrary to Erlachler et al’s theory, male athletes actually exhibited a higher prevalence of disturbed sleep due to anxiety in comparison to the females athletes. Also, it was found that only athletes involved in aerobic sports such as basketball and water polo exhibited negative changes in their performance. Although not all athletes experienced poorer performance, all of them claimed to feel physically tired and experience daytime fatigue after one night of disturbed sleep. Because these athletes have been playing their specific sport for several years, many of them have developed the ability to cope through the physiological and psychological stresses of reduced sleep. Thus, even though they feel tired, they are still able to power through the stressors and perform relatively well. This is seen in the basketball player’s response. 

Through this study, the relationship between precompetition sleep loss and performance is now better understood however, there are many unknowns that still exist. For example, further studies could explore the reason behind why aerobic athletes experience more detriments from reduced sleep in comparison to anaerobic athletes or why male athletes are affected by anxiety more than female athletes. Acquiring this information would educate both athletes and coaches on the importance of sleep and would encourage athletes to inherit better sleep routines in order to optimize performance. Future studies could also explore how many hours of deprived sleep anaerobic athletes can endure before it begins to affect their performance negatively. This gives the athletes an idea of how much sleep they need in order to perform well.

This study was successful in determining the causes and effects that precompetition sleep loss has on varsity athletes. Despite the fact that precompetition sleep loss may not have a huge impact on athletic performance, loss of sleep made the athletes feel physically and mentally exhausted. Although they are able to cope with the exhaustion, coaches should implement better sleep routines and organize later practice and game/competition times for their athletes since many of them complained that early practices/game times contributed to their lack of sleep. For varsity athletes, coaches and teachers should emphasize the importance of time management in order to achieve balance and succeed in both academics and athletics while sleeping enough hours. Additionally since nervousness was the predominating factor experienced by all four of the interviewed athletes, coaches and athletes should develop specific tactics to target anxiety such as meditation or listening to music. Overall, increased sleep is associated with better performance. Thus, ensuring athletes sleep a sufficient amount the night before competitions is beneficial in order for them to mentally and physically feel prepared to perform to the best of their ability.

References:

• Azboy, O., & Kaygisiz, Z. (2009). Effects of sleep deprivation on cardiorespiratory functions of the runners and volleyball players during rest and exercise. Acta Physiologica Hungarica, 96(1), 29-36. doi:10.1556/aphysiol.96.2009.1.3
• Erlacher, D., Ehrlenspiel, F., Adegbesan, O. A., & El-Din, H. G. (2011). Sleep habits in German athletes before important competitions or games. Journal of Sports Sciences, 29(8), 859-866. doi:10.1080/02640414.2011.565782
• Lastella, M., Lovell, G. P., & Sargent, C. (2012). Athletes precompetitive sleep behaviour and its relationship with subsequent precompetitive mood and performance. European Journal of Sport Science, 14(1). doi:10.1080/17461391.2012.660505
• Takeuchi, L., Davis, G. M., Plyley, M., Goode, R., & Shephard, R. J. (1985). Sleep deprivation, chronic exercise and muscular performance. Ergonomics, 28(3), 591-601. doi:10.1080/00140138508963173
• Thun, E., Bjorvatn, B., Flo, E., Harris, A., & Pallesen, S. (2015). Sleep, circadian rhythms, and athletic performance. Sleep Medicine Reviews, 23(1), 1-9. doi:10.1016/j.smrv.2014.11.003
• Zielinski, M. R., McKenna, J. T., & McCarley, R. W. (2016). Functions and Mechanisms of Sleep. Aims Neurosci., 3(1), 67-104. doi:10.3934/Neuroscience.2016.1.67

Interview Questions

1. What is your gender?
2. What sport do you play?
3. How long have you played this sport?
4. On average how many hours of sleep do you get a night
5. How do you feel before games/competitions?
6. Does it affect your sleep (how you feel about games)?
7. On days where you get very little sleep, do you think it has an affect on your performance? How?
8. Are there any other factors that contribute to your sleep loss?
9.  Do you have a preferred game time (morning, afternoon, evening) where you feel your performance is best?
10. How do you sleep when you are in a new environment?