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?