Effects Of Sleep Deprivation On Exercise And Performance

Physiological and Psychological Effects of Sleep Deprivation on Exercise

Question:

Discuss about the Exercise Physiology for Risks and Mitigation.

The purpose of this study is to learn of effects of sleep deprivation on exercise or effects of exercise after sleep and all these based on performance. My expectation was to find out whether it is true that enough sleep is important to sustain peak endurance during exercise for better performance as coaches and athletes agree on this factor. Does sleep deprivation really has any direct effect on exercise and performance?

Adequate sleep is important to sustain peak endurance during exercise for better performance as coaches and athletes agree on this factor. However, the physiological and psychological direct effects of sleep deprivation are yet to be established. There is no proper measurement of effects of sleep deprivation on exercise or effects of exercise after sleep. Sleep deprivation results to dramatic psychological changes in terms of performance on visual and memory task decreasing as well as reaction to time (Walter 1978). However, in comparison to physiological changes, sleep loss does not have an apparent effect on a person physiologically. The connection between sleep loss and its effects on performance is yet to be proved and be agreed on therefore making the findings to be inconclusive and at conflict. There is no proper measurement of effects of sleep deprivation on exercise or effects of exercise after sleep and all these based on the overall performance. It is noted that physiological correlates of exercise performance can be affected by sleep deprivation .Variety of studies have been made concerning sleep deprivation and its effect on performance and exercise but none has had an established conclusive answer (Doran 2001).

The two major studies that I used to explain my hypothesis is; 1. Exercise after sleep deprivation whereby I found out that as much as enough sleep is important to sustain peak endurance during exercise for better performance as coaches and athletes agree on this factor. However, the physiological and psychological direct effects of sleep deprivation are yet to be established. There is no proper measurement of effects of sleep deprivation on exercise or effects of exercise after sleep. Sleep deprivation results to dramatic psychological changes in terms of performance on visual and memory task decreasing as well as reaction to time. However, in comparison to physiological changes, sleep loss does not have an apparent effect on a person physiologically.  In this study we look at how physiological effects of sleep loss have an influence over exercise. Various exercises from mid to maximal intensities were done so as to measure the responses to cardiovascular, metabolic and respiratory processes (Dempsey 1977). 2. The second study was on one night of sleep deprivation decreasing treadmill endurance performance. Here the aim was to test this hypothesis and investigate the effects of one night sleep deprivation on endurance in the running performance. After an experiment was performed, my hypothesis was supported and shows that with the 30 hours of sleep deprivation, there was a major effect on endurance performance of running in the treadmill. Another discovery was that participants’ perception of effort had an effect on performance as there was decrease in the endurance performance following the night without sleep (Brodan et al 1969).

Studies on Sleep Deprivation and Exercise Performance

The participants in my study were eleven recreational active and healthy males were picked randomly to complete the experiment in random trials separated by 7 days. One after normal sleep and another following a 30 hour without sleep.

This study has both independent and dependent variables. The independent variable in this study is whether the participants’ performance and exercise will be affected by sleep deprivation. The dependent variable is the effects of these exercises on the participant’s cardio-respiratory, thermoregulatory and perception of effort responses during intense exercise.

This experiment was done after an acute sleep deprivation process of 30 hours and results taken before, during and after the exercises. The experiment was based on random trials separated by 7 days. One after normal sleep and the other was following a 30 hour without sleep.  Breathing was measured by use of a spirometer. The expired gas samples from breathing were put into test and it was noted that after the exercise the breathing effort was labored. An experiment was done to eleven active and healthy male participants to show submaximal exercise after sleep loss. The experiment was to investigate the effects of sleep deprivation and the after effects manifested after the deprivation. The exercise was to take seven days and the participants were to be monitored every day for the seven days. Before the exercise the participants were familiarized with the experiment procedures before undertaking the exercise. Daily exercises were required for the seven day experiment to see both physiological and psychological responses of each participant (Doran 2001). Food was reduced to a light breakfast which the participants ate every four hours before each experiment.

All exercises were done on a treadmill and speed and distance was tested as well as skin temperatures and heart rates. The 30 hours of sleep deprivation had limited effect on cardio-respiratory and thermoregulatory processes even after intense running exercise. The heart rate decreased by 7-8 beats min during the distance test and oxygen intake was also increase due to intensity of the exercise and due to sleep deprivation. 

The risk that was involved in this test was the prolonged sleep deprivation of 30 hours on the participants and subjecting them to very intense treadmill exercise for seven days. These intense approaches could affect endurance performance of the participants. However, the risks were mitigated by randomly separating the trials and splitting the seven days by incorporating rests in between. The participants were also health males who signed a consent contract to undertake the trial. The participants were also provided for estimated energy requirements and control nutritional and hydration status. Water was provided equaling to 35 ml and energy requirements were also available and enough (3280 (209) kcal d-1).

Experiment Design and Results

Findings by use of a table on ratings of perceived exertion (RPE minimum rating6, maximum 20) during light, moderate and heavy exercise before and after sleep deprivation.

During submaximal exercise, sleep deprivation left no changes in all physiological variables as shown in the above table. During maximal exercise, sleep deprivation did not change heart rate and did increase on the perceived exertion ratings in the moderate and heavy exercise (Copes 1972). It is clear to note that the return of perceived exertion to near control levels following a night of sleep shows that recovery from acute sleep deprivation may be rapid.

Sleep deprivation mostly does not affect physical performance but has a direct effect on human cognitive and motor functioning. This has been proved before that sleep deprivation is more psychological than it is physiological. Human cognition is more psychological and motor performance is more physiological. Sleep deprivation has effects on performance and physical exercises and it affects the performance of a person engaging in exercise and the recovery process. Many athletes are affected by sleep and it results to effects on performance and post exercise recovery. There is substantial scientific evidence showing a connection between sleep, metabolic functions and cognitive processes. Sleep deprivation is majorly linked to cognitive impairment which is mostly a psychological function.  Sleep deprivation also affects negatively the metabolic functions and physiological process Armington 1959). Enough sleep has a positive impact on optimal performance as many athletes, coaches and trainers have confirmed. However, more sophisticated methodology is needed to prove this fact as little is known on the connection between sleep and post-exercise recovery and performance. It is noted that physiological correlates of exercise performance can be affected by sleep deprivation. More studies are being made thoroughly to investigate on the connection of sleep to training, PER and performance in exercise (Spielgel 1999).

After the study I got results that agreed with what was in the literature a number of people may be prone to exposure to sleep loss or sleep deprivation based on different situations and circumstances. Despite the claims from different studies made that adequate and quality sleep is important for maximum performance, there is no substantial evidence to prove the same. There is little or no proof to tie sleep deprivation effects on exercise performance. It is noted that physiological correlates of exercise performance can be affected by sleep deprivation. Sleep deprivation can be caused by a variety of factors such as cardiovascular, metabolic and respiratory processes. Sleep deprivation results to dramatic psychological changes in terms of performance on visual and memory task decreasing as well as reaction to time. However, in comparison to physiological changes, sleep loss does not have an apparent effect on a person physiologically. Sleep deprivation mostly does not affect physical performance but has a direct effect on human cognitive and motor functioning. This has been proved before that sleep deprivation is more psychological than it is physiological. Human cognition is more psychological and motor performance is more physiological. . It is possible to endure and tolerate intense exercises even with sleep deprivation in all situations through increased perceived efforts. Many athletes are affected by sleep and it results to effects on performance and post exercise recovery (VanHelder 1989). . Acute sleep deprivation reduces exercise tolerance and therefore affects performance coupled with other various practical situations. These situations that can cause sleep loss are such as military personnel on sustained operations, workers who work on shift patterns and also athletes who travel through different time zones as well as people who suffer from acute insomnia. However, studies regarding performance in exercise after sleep loss are yet to be conclusive and accurate.

During my experiment I faced one limitation and that was conclusive and accurate information regarding effects of sleep deprivation and performance. If I was to do the experiment again I would ensure I have enough information on how acute sleep deprivation could have effect on obtaining maximum performance in exercise. More proof and added information is required to connect sleep deprivation and its effect on physical performance and human cognitive and motor functioning. This will be able to answer if sleep deprivation is psychological or physiological. 

References

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