Journal of Sports Science and Medicine
Journal of Sports Science and Medicine
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©Journal of Sports Science and Medicine (2007) 06, 532 - 537

Research article
Sleep Deprivation Induced Anxiety and Anaerobic Performance
Selma Arzu Vardar1, , Levent Öztürk1, Cem Kurt2, Erdogan Bulut1, Necdet Sut3, Erdal Vardar4
Author Information
1 Department of Physiology, Trakya University Faculty of Medicine, Edirne, Turkey
2 Kırkpınar Physical Education and Sport Department, Trakya University, Edirne, Turkey
3 Department of Bioistatistics, Trakya University Faculty of Medicine, Edirne, Turkey
4 Department of Psychiatry, Trakya University Faculty of Medicine, Edirne, Turkey

Selma Arzu Vardar
✉ Department of Physiology, Trakya University Faculty of Medicine 22030 Edirne, Turkey
Email: arzuvardar@trakya.edu.tr
Publish Date
Received: 08-06-2007
Accepted: 24-09-2007
Published (online): 01-12-2007
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ABSTRACT

The aim of this study was to investigate the effects of sleep deprivation induced anxiety on anaerobic performance. Thirteen volunteer male physical education students completed the Turkish version of State Anxiety Inventory and performed Wingate anaerobic test for three times: (1) following a full-night of habitual sleep (baseline measurements), (2) following 30 hours of sleep deprivation, and (3) following partial-night sleep deprivation. Baseline measurements were performed the day before total sleep deprivation. Measurements following partial sleep deprivation were made 2 weeks later than total sleep deprivation measurements. State anxiety was measured prior to each Wingate test. The mean state anxiety following total sleep deprivation was higher than the baseline measurement (44.9 ± 12.9 vs. 27.6 ± 4.2, respectively, p = 0.02) whereas anaerobic performance parameters remained unchanged. Neither anaerobic parameters nor state anxiety levels were affected by one night partial sleep deprivation. Our results suggest that 30 hours continuous wakefulness may increase anxiety level without impairing anaerobic performance, whereas one night of partial sleep deprivation was ineffective on both state anxiety and anaerobic performance.

Key words: Psychophysiological disorders, mood, insufficient sleep, muscle fatique


           Key Points
  • Short time total sleep deprivation (30 hours) increases state anxiety without any competition stress.
  • Anaerobic performance parameters such as peak power, mean power and minimum power may not show a distinctive difference from anaerobic performance in a normal sleep day despite the high anxiety level induced by short time sleep deprivation.
  • Partial sleep deprivation does not affect anxiety level and anaerobic performance of the next day.

INTRODUCTION

Evidence suggests athletes worry about the effects of inadequate sleep on performance (Leger et al., 2005) although sleep deprivation on physical performance (e.g. anaerobic power, muscle strength, endurance, physiological responses such as heart rate, ventilation, oxygen consumption) is not clearly understood (Martin, 1981; 1986; Rodgers et al., 1995; Souissi et al., 2003; Youngstedt and O’Connor, 1999). Rodgers et al., 1995 reported that 48 hours period of sleep deprivation significantly decreased the physical work tasks requiring 30-45% VO2max without affecting anaerobic power. Further, Souissi et al., 2003 demonstrated that duration of sleepless period may be important as peak power was not affected after 24 hours sleep deprivation but significantly decreased after 36 hours of wakefulness.

In contrast, it is well established that sleep deprivation can result in impairments in affective states (e.g. increased anxiety, depressed mood, anger, tension, frustration and irritability) and cognitive functions (JrLeDuc et al., 2000; Orton and Gruzelier, 1989; Scott et al., 2006). Martin and Gaddis (1981) demonstrated that 30 hours sleep deprivation significantly affected psychological responses without affecting physical performance. According to a recent study, it was found that 56 hours sleep deprivation was associated with a statistically significant increase in self reported symptoms of anxiety (Kahn-Greene et al., 2007).

The relationship between anxiety and athletic performance has been extensively studied (Craft et al., 2003; DeMoja and DeMoja, 1986; Hogg, 1980; Hume et al., 1993; Jones and Hardy, 1988; Kais and Raudsepp, 2004; Pijpers et al., 2005). Additionally, various theoretical models have been proposed to describe the relationship between anxiety and performance (Raglin, 1992; Thelwell and Maynard, 1996; Turner and Raglin, 1996). Inconsistent results have been obtained for the effect of anxiety on athletic performance. Some studies report negative correlation between anxiety and athletic performance (DeMoja and DeMoja, 1986; Hume et al., 1993). For instance, Hume et al., 1993 demonstrated a significant negative correlation between athletic attainment and anxiety level in 106 female gymnasts. In contrast, some studies showed positive correlation, whereby anxiety appeared to have helped performance (Kais and Raudsepp, 2004; Parfitt et al., 1995; Parfitt and Pates, 1999). For example, Parfitt and Pates, 1999 showed that increase in somatic anxiety is associated with increase in anaerobic power.

A factor that could influence the strength of anxiety-performance relationships not considered adequately in the literature is the effect of sleep deprivation. Previous studies demonstrated that sleep deprivation is associated with increased anxiety in healthy young adults (Dinges et al., 1997; Kahn-Greene et al., 2007; Sagaspe et al., 2006). Sleep deprivation is associated with higher state anxiety levels which in turn alter athletic performance. Pedlar et al., 2007 demonstrated that it was possible to continuously decrease sleep time to an extremely low level for a prolonged period (44 days) and simultaneously maintain a very high work load; however, this pattern may have adverse affects on mood. Therefore, it has been thought that additional studies of sleep deprivation may help to elucidate the association between anxiety and athletic performance. We hypothesize that duration of sleep deprivation in the night preceding anaerobic athletic event is an effective variable in determining anxiety level and thus anaerobic performance. The aim of this study was to investigate the possible short-term total and partial sleep deprivation induced anxiety on anaerobic performance parameters such as peak power and mean power obtained from the 30-second Wingate Test in the same study population.

METHODS

Participants

Thirteen healthy male students attending school of physical education accepted to participate in the study. As the Wingate test requires maximum power, only students who exercise regularly were accepted to the study. In addition just the males were included in the study in order to assure that the findings following sleep deprivation are not affected from gender differences (Caldwell and Leduc, 1998). Details of the study were explained to each participant and signed informed consents were obtained. The study was approved by the local ethics committee of Trakya University. A self-administered questionnaire was used to assess age, weight, height, with their participation age to sports, and the amount of training per week. The mean (±SD) age, height, BMI, participation age in sports, duration of training and the amount of training of the participants were given in Table 1. BMI was calculated as weight in kilograms per height in square meters. Since participants were unfamiliar with the procedures, the Wingate Anaerobic Test was applied to all participants two weeks prior to the experimental trials in order to provide familiarity.

Participants also kept a diary of their activities during the three days before the baseline night. Participants’ time of going to bed varied between 10 00 p.m. and 11 00 p.m. The time of waking up varied between 07 00 a.m. and 08 00 a.m.

Inclusion criteria

All participants were non-smokers and they took no medication or alcohol in order not to affect the measurements of anxiety (Crome and Bloor, 2005). No participant declared a psychiatric or another illness. In order to ensure that the study group shows homogeneity with respect to chronotype, morningness-eveningness questionnaire of Horne and Östberg, 1976 was filled out and participants with similar characteristics were included. This questionnaire establishes five behavioural categories: definitively morning types (score=70-86), moderately morning types (score=59-69), neither types (score=42-58), moderately evening types (score=31-41) and definitively evening types (score=16-30). The reliability of the Turkish version of the Horne and Östberg questionnaire has been established in a previous study (Punduk et al., 2005). Moderately morning types (n = 6) and neither types (n = 7) were included in this study.

Subjective sleep quality of participants was investigated using Pittsburg Sleep Quality Index (PSQI) that is a self-noted questionnaire that assesses sleep quality and sleep disturbance over one- month period (Buysse et al., 1989). It comprises 19 individual items generating seven “component ”scores: subjective sleep quality, sleep latency, sleep duration, habitual sleep efficiency, sleep disturbances, use of sleeping medication and daytime dysfunction. The sum of scores for these seven components yields one PSQI global score. In addition to showing global scores as a continuous variable, participants were dichotomized into “good ”sleepers (PSQI < 5) and “poor ”sleepers (PSQI > 5) according to previous methodology. We included good sleepers in our study. PSQI scores of all participants were lower than 5 in our study group. The mean (±SD) PSQI scores of participants were given in Table 1. A Turkish translation and reliability and validity studies of this scale were performed in a Turkish sample (Agargun et al., 1996).

Study design

The protocol included three parts: (1) baseline measurements, (2) measurements following short-term total (30 hours) sleep deprivation, (3) measurements following partial sleep deprivation (Figure 1). With respect to duration, total sleep deprivation may be divided into short-term (≤ 45 hours) and long-term (> 45 hours) deprivation. Partial sleep deprivation refers to sleep duration less than 5 hours per night (Pilcher and Huffcutt, 1996).

The first part of the study was performed in the next day following the normal habitual sleep period. Following baseline measurements, participants remained awake whole night and day under the constant observation of two investigators in our laboratory. During the sleep deprivation period, the participants spent their time playing table games, reading books or watching television. They were restricted from taking caffeine, tea or other stimulants. The second Wingate Test was performed for each participant at the same time period (14.00-16.00) of the following day.

In the last section, all participants exposed to partial sleep deprivation at least two weeks after total deprivation experiment. They were observed by two investigators. The participants were allowed to sleep between 03.00-07.00 am. They were taken to the exercise laboratory at 08.00 am and kept awake until the Wingate Test was performed. During this period, participants were able to freely engage in a variety of activities (e.g. play computer games, read books, watch television). State anxiety scale and subjective sleepiness by visual analogue scale (VAS) were recorded before each Wingate test. The participants had isocaloric meals in lunch and dinner during the study protocol in order to assure that meals eaten do not affect sleep deprivation (Smith and Maben, 1993).

Anaerobic test

The Wingate test consisted of a 30-second supramaximal cycling against a resistance load. Each test was performed on a Monark cycle ergometer (Model 894-E, Sweden) and for each participant the load was calculated as 0.090 kg x.kg-1 body mass. The participants warmed up by pedalling for 3 min against a 30 watt load. After 5 min rest period, by the command “start ”the participant began pedalling as fast as possible against a predetermined work load until the end of the test period. Strong verbal motivation was given to participants to maintain maximal pedalling rate during the test. The data were used to calculate peak power and mean power as reported by Bar-Or, 1987.

State-trait anxiety scale (STAI)

The STAI was developed by Spielberger et al., 1970 to measure state and trait anxiety. Each participant’s level of anxiety was assessed using the STAI, which consists of 20 items, each representative of a category of anxiety symptoms. Oner and LeCompte, 1985 determined the reliability and validity of the STAI for a Turkish population. Participants completed state anxiety scale before each Wingate test. Trait anxiety inventory was completed only before the first anaerobic test.

Sleepiness

Subjective sleepiness was recorded using VAS. Participants rated and reported how much sleepy they felt on a 100 mm horizontal line from “very alert ”on the left and “very sleepy ”on the right. Sleepiness score was measured as the distance of mark from the left in millimetres.

Statistical analysis

The state anxiety score was used as the basis to calculate the power of this study. The power of this study was 85.6% based on the maximum difference in the mean state anxiety score =17.6 between levels, standard deviation=12.9, type I error=5%, n=13.

General characteristics of the participants were presented as mean ± standard deviations and range. Normality distribution of variables was tested using Kolmogorov Smirnov test. The effects of three different sleep conditions on anaerobic performance and anxiety were evaluated by repeated measures analysis of variance (ANOVA) test, and then Bonferroni post-hoc test was used when the significance difference was obtained. Sleepiness was evaluated by Freidman repeated measures ANOVA test due to non-normal distribution, and then Bonferroni post-hoc test was used when significant difference was obtained. P-value <0.05 was considered statistically significant. Statistica 7.0 statistical software was used for statistical analyses.

RESULTS

Trait anxiety scores (33.11 ± 5.13) verified that our study group was homogenous in terms of general anxiety level. Mean state anxiety scores after total sleep deprivation were significantly higher when compared to the baseline and partial sleep deprivation measurements (Table 2). VAS scores of total sleep deprivation day were significantly higher than the baseline measurements (Table 2). No significant difference was observed between the peak power, mean power and anaerobic fatigue values recorded during Wingate Test after the baseline, total and partial sleep deprivation nights (Table 2).

DISCUSSION

The main finding of this study is that anaerobic performance parameters remained unchanged following 30 hours sleep deprivation, although state anxiety levels of the participants were significantly higher during the same period. In addition, one night of partial sleep deprivation was not associated with enhanced anxiety or impaired anaerobic performance. No statistically significant alterations in anaerobic performance resulting from one night of total or partial sleep loss were found.

Numerous studies have examined the relationship between anxiety and performance (DeMoja and DeMoja, 1986; Hogg, 1980; Hume et al., 1993; Jones and Hardy, 1988; Kais and Raudsepp, 2004; Parfitt et al., 1995; Parfitt and Pates, 1999; Pijpers et al., 2005). Sleep deprivation was not evaluated as a factor that could affect anxiety in studies focused on anxiety- performance relationship whereas some studies demonstrated that sleep deprivation was reported to produce anxiety in humans (Dinges et al., 1997; Kahn-Greene et al., 2007; Sagaspe et al., 2006). In the present study, sleep deprivation was evaluated as an anxiety inducer. The increase in anxiety levels was originally due to total sleep deprivation rather than competition stress or a pathological state.

It is questionable that whether these increased anxiety levels were high enough to influence anaerobic performance parameters (peak power, mean power and anaerobic fatigue). The peak power represents the highest maximal voluntary contraction during any 3- to 5- second period of the Wingate test. Peak power may be affected from central (motivation) and peripheral (neuromuscular) factors (Bernard et al., 1998). Our study revealed that increased anxiety levels resulting from total sleep deprivation do not appear to play any central or peripheral effect in healthy participants.

In our study, the effect of sleep deprivation on anaerobic performance was evaluated by using a supramaximal exercise test. It was found that sleep deprivation did not affect anaerobic performance. In previous studies, the effect of sleep deprivation on performance was examined after treadmill walking at different levels of VO2 max, and negative effects were reported (Martin, 1981; Rodgers, 1995). It seems that, there has been conflicting findings on the effect of sleep deprivation on physical performance. One of the reasons of this conflict may be examining the physical performance by different standardised physiological tests. Another reason of getting conflicting findings on the effect of sleep deprivation on physical performance may be the duration of sleep deprivation.

In the present study, both total and partial sleep deprivation were investigated in the same study population. Several studies (Rodgers et al., 1995; Symons et al., 1988; Takeuchi et al., 1985) investigated especially the effects of total sleep deprivation on anaerobic performance. In general, no deterioration was revealed in anaerobic performance following total sleep deprivation. However, a recent study reported that 24 h sleep deprivation unaffected but 36 h wakefulness decreased anaerobic performance (Souissi et al., 2003). In a previous study, Mougin et al., 1996 investigated the effects of partial sleep deprivation on the next day anaerobic performance in 8 highly trained athletes. Their findings revealed that partial sleep deprivation does not contribute to differences in various aspects of supramaximal exercise including mean power and peak power. In the light of above considerations, we suggest that short-term total or partial sleep deprivation is not effective on anaerobic performance, even though anxiety levels may be increased to some extent.

Anaerobic performance parameters could obtain specific information for supramaximal exercise levels of individuals. We performed only one test in a day and all tests were taken at the same time period (14.00-16.00 p.m.) to prevent circadian variation effects (time-of-day effect). Bernard et al., 1998 demonstrated the time-of-day effect in the maximal anaerobic power of cycle test. They reported that there were significant differences between the morning and the afternoon measurements whereas no differences were observed between 14.00 and 18.00 hours. We preferred the same time period in order to remove the time-of-day effect.

In this study anxiety and performance responses were obtained in the laboratory environment. Performing the measurements in laboratory provided us a more tightly controlled environment. However, in terms of ecological validity, laboratory environment may be disadvantageous as sportive environment is ever-changing with its weather conditions and existence of other competitors. A recent study revealed that sleep time was positively related to vigor and inversely related to fatigue throughout an expedition to the South Pole in winter (Pedlar et al. 2007). Laboratory assessment isolates the participant from all these ecological conditions. This may reduce the ecological validity of this study.

There are several limitations of the study. First, we measured state anxiety only once prior to anaerobic measurements. Continuous monitorization of anxiety by certain intervals during whole day would be beneficial. Secondly, our study includes subjective anxiety evaluation; further studies are needed to demonstrate objective self evaluations such as heart rate, blood pressure and muscular tension to confirm our findings. Additionally, our study population covered only male participants. Therefore, extrapolation of these results to female athletes may lead to misinterpretations.

Another confounding factor may be the order effect. All participants were subjected to total sleep deprivation and then to partial sleep deprivation. There were two weeks between these two deprivation protocols. We think that an alternate model (first partial, then total) would give the same results as two weeks period is long enough for recovery.

CONCLUSION

In summary, many athletes can worry about the effects of inadequate sleep on athletic performance in sports activities. We investigated the effects of total and partial sleep deprivation induced anxiety without any competition stress on anaerobic parameters. We showed that only short-term total (30 hours) sleep deprivation but not partial sleep deprivation may enhance anxiety in healthy participants. Finally, we suggest that short-term total sleep deprivation may alter self reported anxiety levels to some extent which seems to be ineffective on anaerobic performance.

AUTHOR BIOGRAPHY

Journal of Sports Science and Medicine Selma Arzu Vardar
Employment: Ass. Prof., Department of Physiology, Trakya University, Edirne, Turkey.
Degree: MD,PhD
Research interests: The effect of exercise on sleeping, the response of women to exercise.
E-mail: arzuvardar@trakya.edu.tr
 

Journal of Sports Science and Medicine Levent Öztürk
Employment: Asc. Prof., Department of Physiology, Trakya University, Edirne, Turkey.
Degree: MD
Research interests: Sleep physiology, sleep and exercise interactions, sleep related breathing disorders.
E-mail: leventozturk@trakya.edu.tr
 

Journal of Sports Science and Medicine Cem Kurt
Employment: Trakya University Physical Education and Sport Department, Edirne, Turkey.
Degree: MSc
Research interests: Plyometric exercise.
E-mail: cemkurt@hotmail.com
 

Journal of Sports Science and Medicine Erdogan Bulut
Employment: PhD Student, Department of Physiology, Trakya University, Edirne, Turkey.
Degree: MSc
Research interests: Exercise induced changes in ouditory brainstem evoked potantials.
E-mail: erbulut2004@yahoo.com
 

Journal of Sports Science and Medicine Necdet Sut
Employment: Ass. Prof., Trakya University, Department of Bioistatistics Edirne, Turkey.
Degree: PhD
Research interests: Multivariate statistical analysis, application of neural networks and bayesian networks in medicine.
E-mail: necdetsut@yahoo.com
 

Journal of Sports Science and Medicine Erdal Vardar
Employment: Asc. Prof., Trakya University, Faculty of Medicine, Department of Psychiatry, Edirne, Turkey.
Degree: MD
Research interests: Eating disorders, exercise psychology.
E-mail: erdalvardar@trakya.edu.tr
 
 
REFERENCES
Journal of Sports Science and Medicine Agargün M.Y., Kara H., Anlar O. (1996) The validity and reliability of the Pittsburgh Sleep Quality Index. Turkish Journal of Psychiatry 7, 107-115.
Journal of Sports Science and Medicine Bar-Or O. (1987) The Wingate anaerobic test. An update on methodology, reliability and validity. Sports Medicine 4, 381-394.
Journal of Sports Science and Medicine Baumeister R.F. (1984) Choking under pressure: self-consciousness and paradoxical effects of incentives on skillful performance. Journal of Personality and Social Psychology 46, 610-620.
Journal of Sports Science and Medicine Bernard T., Giacomoni M., Gavarry O., Seymat M., Falgairette G. (1998) Time-of-day effects in maximal anaerobic leg exercise. European Journal of Applied Physiology and Occupational Physiology 77, 133-138.
Journal of Sports Science and Medicine Buysse D.J., Reynolds C.F., Monk T.H., Berman S.R., Kupfer D.J. (1989) The Pittsburgh Sleep Quality Index: a new instrument for psychiatric practice and research. Psychiatry Research 28, 193-213.
Journal of Sports Science and Medicine Caldwell J.A., Leduc P.A. (1998) Gender influences on performance, mood and recovery sleep in fatigued aviators. Ergonomics 41, 1757-1770.
Journal of Sports Science and Medicine Craft L.L., Magyar T.M., Becker B.J., Feltz D.L. (2003) The relationship between the Competitive State Anxiety Inventory-2 and sport performance: a meta-analysis. Journal of Sport and Exercise Psychology 25, 44-65.
Journal of Sports Science and Medicine Crome I., Bloor R. (2005) Substance misuse and psychiatric comorbidity in adolescents. Current Opinion in Psychiatry 18, 435-439.
Journal of Sports Science and Medicine DeMoja C.A., DeMoja G. (1986) State-trait anxiety and motocross performance. Perceptual and Motor Skills 62, 107-110.
Journal of Sports Science and Medicine Dinges D.F., Pack F., Williams K., Gillen K.A., Powell J.W., Ott G.E., Aptowicz C., Pack A.I. (1997) Cumulative sleepiness, mood disturbance, and psychomotor vigilance performance decrements during a week of sleep restricted to 4-5 hours per night. Sleep 20, 267-277.
Journal of Sports Science and Medicine Hogg J.M. (1980) Anxiety and the competitive swimmer. Canadian Journal of Applied Sport Sciences 5, 183-187.
Journal of Sports Science and Medicine Horne J.A., Östberg O. (1976) A self assessment questionnaire to determine morningness-eveningness in human circadian rhythms. International Journal of Chronobiology 4, 97-110.
Journal of Sports Science and Medicine Hume P.A., Hopkins W.G., Robinson D.M., Robinson S.M., Hollings S.C. (1993) Predictors of attainment in rhythmic sportive gymnastics. Journal of Sports Medicine and Physical Fitness 33, 367-377.
Journal of Sports Science and Medicine Jones J.G., Hardy L. (1988) The effects of anxiety upon psychomotor performance. Journal of Sports Science 6, 59-67.
Journal of Sports Science and Medicine JrLeDuc P.A., Caldwell J.A., Ruyak P.S. (2000) The effects of exercise as a countermeasure for fatigue in sleep-deprived aviators. Military Psychology 12, 249-266.
Journal of Sports Science and Medicine Kahn-Greene E.T., Killgore D.B., Kamimori G.H., Balkin T.J., Killgore W.D. (2007) The effects of sleep deprivation on symptoms of psychopathology in healthy adults. Sleep Medicine 8, 215-221.
Journal of Sports Science and Medicine Kais K., Raudsepp L. (2004) Cognitive and somatic anxiety and self-confidence in athletic performance of beach volleyball. Perceptual and Motor Skills 98, 439-449.
Journal of Sports Science and Medicine Leger D., Metlaine A., Choudat D. (2005) Insomnia and sleep disruption: Relevance for athletic performance. Clinics in Sports Medicine 24, 269-285.
Journal of Sports Science and Medicine Martin B.J. (1981) Effect of sleep deprivation on tolerance of prolonged exercise:. European Journal of Applied Physiology and Occupational Physiology 47, 345-354.
Journal of Sports Science and Medicine Martin B.J. (1986) Sleep deprivation and exercise. Exercise and Sport Sciences Reviews 14, 213-229.
Journal of Sports Science and Medicine Martin B.J., Gaddis G.M. (1981) Exercise after sleep deprivation. Medicine and Science in Sports and Exercise 13, 220-223.
Journal of Sports Science and Medicine Mougin F., Bourdin H., Simon-Rigaud M.L., Didier J.M., Toubin G., Kantelip J.P. (1996) Effects of a selective sleep deprivation on subsequent anaerobic performance. International Journal of Sports Medicine 17, 115-119.
Journal of Sports Science and Medicine Oner N., LeCompte A. (1985) State-trait anxiety inventory hand book. Istanbul. Bogazici University Press.
Journal of Sports Science and Medicine Orton D.I., Gruzelier J.H. (1989) Adverse changes in mood and cognitive performance of house officers after night duty. British Medical Journal 298, 21-23.
Journal of Sports Science and Medicine Parfitt G., Hardy L., Pates J. (1995) Somatic anxiety, physiological arousal and performance: Differential effects upon a high anaerobic, low memory demand task. International Journal of Sport Psychology 26, 196-213.
Journal of Sports Science and Medicine Parfitt G., Pates J. (1999) The effects of cognitive and somatic anxiety and self-confidence on components of performance during competition. Journal of Sports Science 17, 351-356.
Journal of Sports Science and Medicine Pedlar C.R., Lane A.M., Lloyd J.C., Dawson J., Emegbo S., Whyte G.P., Stanley N. (2007) Sleep profiles and mood States during an expedition to the South Pole. Wilderness Environmental Medicine 18, 127-132.
Journal of Sports Science and Medicine Pijpers J.R., Oudejans R.R., Bakker F.C. (2005) Anxiety-induced changes in movement behaviour during the execution of a complex whole-body task. Quarterly Journal of Experimental Psychology Section A-Human Experimental Psychology 58, 421-445.
Journal of Sports Science and Medicine Pilcher J.J., Huffcutt A.I. (1996) Effects of sleep deprivation on performance: a meta-analysis. Sleep 19, 318-326.
Journal of Sports Science and Medicine Punduk Z., Gur H., Ercan I. (2005) A reliability study of the Turkish version of the morningness-eveningness questionnaire. Turkish Journal of Psychiatry 16, 40-45.
Journal of Sports Science and Medicine Raglin J.S. (1992) Anxiety and sport performance. Exercise and Sport Sciences Reviews 20, 243-274.
Journal of Sports Science and Medicine Rodgers C.D., Paterson D.H., Cunningham D.A., Noble E.G., Pettigrew F.P., Myles W.S., Taylor A.W. (1995) Sleep deprivation: effects on work capacity, self-paced walking, contractile properties and perceived exertion. Sleep 18, 30-38.
Journal of Sports Science and Medicine Sagaspe P., Sanchez-Ortuno M., Charles A., Taillard J., Valtat C., Bioulac B., Philip P. (2006) Effects of sleep deprivation on Color-Word, Emotional, and Specific Stroop interference and on self-reported anxiety. Brain and Cognition 60, 76-87.
Journal of Sports Science and Medicine Scott J.P.R., McNaughton L.R., Polman R.C.J. (2006) Effects of sleep deprivation and exercise on cognitive, motor performance and mood. Physiology and Behavior 87, 396-408.
Journal of Sports Science and Medicine Smith A., Maben A. (1993) Effects of sleep deprivation, lunch, and personality on performance, mood, and cardiovascular function. Physiology and Behavior 54, 967-972.
Journal of Sports Science and Medicine Souissi N., Sesboue B., Gauthier A., Larue J., Davenne D. (2003) Effects of one night’s sleep deprivation on anaerobic performance the following day. European Journal of Applied Physiology 89, 359-366.
Journal of Sports Science and Medicine Spielberger C., Gorsuch R., Lushene R. (1970) Manual for stait-trait anxiety inventory. Palo Alto, California. Consulting Psychologist Press.
Journal of Sports Science and Medicine Symons J.D., VanHelder T., Myles W.S. (1988) Physical performance and physiological responses following 60 hours of sleep deprivation. Medicine and Science in Sports and Exercise 20, 374-380.
Journal of Sports Science and Medicine Takeuchi L., Davis G.M., Plyley M., Goode R., Shephard R.J. (1985) Sleep deprivation, chronic exercise and muscular performance. Ergonomics 28, 591-601.
Journal of Sports Science and Medicine Thelwell R.C., Maynard I.W. (1996) Anxiety-performance relationships in cricketers: testing the zone of optimal functioning hypothesis. Perceptual and Motor Skills 87, 675-689.
Journal of Sports Science and Medicine Thomas M., Sing H., Belenky G., Holcomb H., Mayberg H., Dannals R., Wagner H., Thorne D., Popp K., Rowland L., Welsh A., Balwinski S., Redmond D. (2003) Neural basis of alertness and cognitive performance impairments during sleepiness. I. Effects of 24 h of sleep deprivation on waking human regional brain activity:. Journal of Sleep Research 9, 335-352.
Journal of Sports Science and Medicine Turner P.E., Raglin J.S. (1996) Variability in precompetition anxiety and performance in college track and field athletes. Medicine and Science in Sports and Exercise 28, 378-385.
Journal of Sports Science and Medicine Youngstedt S.D., O’Connor P.J. (1999) The influence of air travel on athletic performance. Sports Medicine 28, 197-207.
 
 
 
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