Sports Medicine

, Volume 21, Issue 4, pp 292–312 | Cite as

Circadian Variation in Sports Performance

  • Greg Atkinson
  • Thomas Reilly
Review Article

Summary

Chronobiology is the science concerned with investigations of time-dependent changes in physiological variables. Circadian rhythms refer to variations that recur every 24 hours. Many physiological circadian rhythms at rest are endogenously controlled, and persist when an individual is isolated from environmental fluctuations. Unlike physiological variables, human performance cannot be monitored continuously in order to describe circadian rhythmicity. Experimental studies of the effect of circadian rhythms on performance need to be carefully designed in order to control for serial fatigue effects and to minimise disturbances in sleep. The detection of rhythmicity in performance variables is also highly influenced by the degree of test-retest repeatability of the measuring equipment.

The majority of components of sports performance, e.g. flexibility, muscle strength, short term high power output, vary with time of day in a sinusoidal manner and peak in the early evening close to the daily maximum in body temperature. Psychological tests of short term memory, heart rate-based tests of physical fitness, and prolonged submaximal exercise performance carried out in hot conditions show peak times in the morning. Heart rate-based tests of work capacity appear to peak in the morning because the heart rate responses to exercise are minimal at this time of day. Post-lunch declines are evident with performance variables such as muscle strength, especially if measured frequently enough and sequentially within a 24-hour period to cause fatigue in individuals. More research work is needed to ascertain whether performance in tasks demanding fine motor control varies with time of day.

Metabolic and respiratory rhythms are flattened when exercise becomes strenuous whilst the body temperature rhythm persists during maximal exercise. Higher work-rates are selected spontaneously in the early evening. At present, it is not known whether time of day influences the responses of a set training regimen (one in which the training stimulus does not vary with time of day) for endurance, strength, or the learning of motor skills.

The normal circadian rhythms can be desynchronised following a flight across several time zones or a transfer to nocturnal work shifts. Although athletes show all the symptoms of ‘jet lag’ (increased fatigue, disturbed sleep and circadian rhythms), more research work is needed to identify the effects of transmeridian travel on the actual performances of elite sports competitors. Such investigations would need to be chronobiological, i.e. monitor performance at several dmes on several post-flight days, and take into account direction of travel, time of day of competition and the various performance components involved in a particular sport.

Shiftwork interferes with participation in competitive sport, although there may be greater opportunities for shiftworkers to train in the hours of daylight for individual sports such as cycling and swimming. Studies should be conducted to ascertain whether shiftwork-mediated rhythm disturbances affect sports performance.

Individual differences in performance rhythms are small but significant. Circadian rhythms are larger in amplitude in physically fit individuals than sedentary individuals. Athletes over 50 years of age tend to be higher in ‘momingness’, habitually scheduling relatively more training in the morning and selecting relatively higher work-rates during exercise compared with young athletes. These differences should be recognised by practitioners concerned with organising the habitual regimens of athletes.

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References

  1. 1.
    Haus E, Touitou Y. Principles of clinical chronobiology. In: Touitou Y, Haus E, editors. Biological rhythms in clinical and laboratory medicine. Berlin: Springer-Verlag, 1992: 6–34CrossRefGoogle Scholar
  2. 2.
    Campbell J. Winston Churchill’s afternoon nap. London: Aurum Press, 1988Google Scholar
  3. 3.
    Cannon WB. The wisdom of the body. New York: Norton, 1939Google Scholar
  4. 4.
    Minors D, Waterhouse J. Circadian rhythms and the human. London: Wright PSG, 1981Google Scholar
  5. 5.
    Reilly T. Human circadian rhythms and exercise. Crit Rev Biomed Eng 1990; 18: 165–80PubMedGoogle Scholar
  6. 6.
    Halberg F. Physiologic 24-hour periodicity in humans beings and mice, the lighting regimen and daily routine. In: Withrow RB, editor. Photoperiodism and related phenomena in plants and animals. Washington: American Association for the Advancement of Science, 1959: 803–78Google Scholar
  7. 7.
    Wolf W. Rhythmic functions in living systems. Ann NY Acad Sci 1962; 98: 753–1326Google Scholar
  8. 8.
    Reilly T, Young K, Seddon R. Investigation of biorhythms in female athletic performance. Appl Ergon 1983; 14: 215–7PubMedCrossRefGoogle Scholar
  9. 9.
    Quigley BM. Biorhythms and Australian track and field records. J Sports Med Phys Fitness 1981; 21: 81–9PubMedGoogle Scholar
  10. 10.
    Mills JN, Minors DS, Waterhouse JM. The effects of sleep upon human circadian rhythms. Chronobiologia 1978; 5: 14–27PubMedGoogle Scholar
  11. 11.
    Halberg F, Vallbona C, Dietlin LF. Human circadian circulatory rhythms during weightlessness in extraterrestial flight or bedrest with and without exercise. Space Life Sci 1970; 2: 18–32PubMedGoogle Scholar
  12. 12.
    Wever R. Influence of physical workload on free running circadian rhythms of man. Pflugers Arch 1979; 38: 119–26CrossRefGoogle Scholar
  13. 13.
    Green DJ, Gillette R. Circadian rhythm of firing rate recorded from single cells in the rat suprachiasmatic brain slice. Brain Res 1982; 245: 198–200PubMedCrossRefGoogle Scholar
  14. 14.
    Ralph MR, Foster RG, Davis FC, et al. Transplanted suprachiasmatic nucleus determines circadian period. Science 1990; 247: 975–8PubMedCrossRefGoogle Scholar
  15. 15.
    Aschoff J. Circadian rhythms in man. Science 1965; 148: 1427–32PubMedCrossRefGoogle Scholar
  16. 16.
    Arendt J. The pineal. In: Touitou Y, Haus E, editors. Biological rhythms in clinical and laboratory medicine. Berlin: Springer-Verlag, 1992; 348–62CrossRefGoogle Scholar
  17. 17.
    Theron JJ, Oosthuizen JMC, Rautenbach MM. Effect of physical exercise on plasma melatonin levels in normal volunteers. S Afr Med J 1984; 66: 838–41PubMedGoogle Scholar
  18. 18.
    Monteleone P, Maj M, Fusco M, et al. Physical exercise at night blunts the nocturnal increase of plasma melatonin levels in healthy humans. Life Sci 1990; 47: 1989–95PubMedCrossRefGoogle Scholar
  19. 19.
    Piercy J, Lack L. Daily exercise can shift the endogenous circadian rhythm. Sleep Res 1988; 17: 393Google Scholar
  20. 20.
    Akerstedt T. Altered sleep/wake pattems and circadian rhythms. Acta Physiol Scand Suppl 1979; 469: 1–48PubMedGoogle Scholar
  21. 21.
    Smolensky MH, Tatar SE, Bergman SA, et al. Circadian rhythmic aspects of human cardiovascular function: a review by chronobiologic statistical methods. Chronobiologia 1976; 3: 337–71PubMedGoogle Scholar
  22. 22.
    Pickering TG. The influence of daily activity on ambulatory blood pressure. Am Heart J 1988; 116: 1141–5PubMedCrossRefGoogle Scholar
  23. 23.
    Baumgart P, Walger P, Fuchs G, et al. Twenty-four-hour blood pressure is not dependent on endogenous circadian rhythm. J Hypertens 1989; 7: 331–4PubMedCrossRefGoogle Scholar
  24. 24.
    Zulch KJ, Hossman V. 24-hour rhythm of human blood pressure. Ger Med Monthly 1967; 12: 513–8Google Scholar
  25. 25.
    Atkinson G, Witte K, Nold G, et al. Effects of age on circadian blood pressure and heart rate rhythms in primary hypertensive patients. Chronobiol Int 1994; 11: 35–44PubMedCrossRefGoogle Scholar
  26. 26.
    Gaultier C, Reinberg A, Girard F. Circadian rhythms in lung resistance and dynamic lung compliance of healthy children. Effect of two bronchodilators. Respir Physiol 1977; 31: 169–82PubMedCrossRefGoogle Scholar
  27. 27.
    Smolensky MH, Scott PH, Barnes PJ, et al. The chronopharmacology and chronotherapy of asthma. Annu Rev Chronopharmacol 1986; 2: 229–73Google Scholar
  28. 28.
    Smolensky MH, Alonzo GED. Nocturnal asthma: mechanisms and chronotherapy. In: Touitou Y, Haus E, editors. Biological rhythms in clinical and laboratory medicine. Berlin: Springer-Verlag 1992; 453–69CrossRefGoogle Scholar
  29. 29.
    Swoyer J, Haus E, Lakatua D, et al. Chronobiology in the clinical laboratory. In: Haus H, Kabat H, editors. Chronobiology 1982–1983. New York: Karger, 1984; 533–43Google Scholar
  30. 30.
    Mejean L, Kolopp M, Drouin P. Chronobiology, nutrition and diabetes mellitus. In: Touitou Y, Haus E, editors. Biological rhythms in clinical and laboratory medicine. Berlin: Springer-Verlag, 1992; 375–85CrossRefGoogle Scholar
  31. 31.
    Schlierf G. Diurnal variations in plasma substrate concentration. Eur J Clin Invest 1978; 8: 59–60PubMedCrossRefGoogle Scholar
  32. 32.
    Veldhuis JD, Johnson ML, Iranmanesh A, et al. Rhythmic and non-rhythmic modes of anterior pituitary hormone release in man. In: Touitou Y, Haus E, editors. Biological rhythms in clinical and laboratory medicine. Berlin: Springer-Verlag, 1992; 277–91CrossRefGoogle Scholar
  33. 33.
    Moore JG. Chronobiology of the gastrointestinal system. In: Touitou Y, Haus E, editors. Biological rhythms in clinical and laboratory medicine. Berlin: Springer-Verlag, 1992; 410–7CrossRefGoogle Scholar
  34. 34.
    Goo RH, Moore JG, Greenberg E, et al. Circadian variation in gastric emptying of meals in man. Gastroenterology 1987: 93; 515–8PubMedGoogle Scholar
  35. 35.
    Touitou Y, Touitou C, Bogdan A, et al. Circadian and seasonal variations of electrolytes in ageing humans. Clin Chim Acta 1989; 180: 245–54PubMedCrossRefGoogle Scholar
  36. 36.
    Robertson WG, Hodgkinson A, Marshall DH. Seasonal variations in the composition of urine from normal subjects: a longitudinal study. Clin Chim Acta 1977; 80: 347–53PubMedCrossRefGoogle Scholar
  37. 37.
    Wisser H, Breur H. Circadian changes of clinical, chemical and endocrinological parameters. J Clin Chem Clin Biochem 1981; 19: 323–8PubMedGoogle Scholar
  38. 38.
    Atkinson G, Coldwells A, Reilly T, et al. An age-comparison of circadian rhythms in physical performance measures. In: Harris S, Era P, Suominen H, et al., editors. Towards healthy aging — international perspectives. Part 1. Physiological and biomedical aspects. Albany: Center for the Study of Aging, 1994; 205–18Google Scholar
  39. 39.
    Akerstedt T, Froberg JE. Interindividual differences in circadian patterns of catecholamine excretion, body temperature, performance and subjective arousal. Biol Psychology 1976; 4: 277–92CrossRefGoogle Scholar
  40. 40.
    Hoddes E, Zarcone V, Smythe HR, et al. Quantification of sleepiness: a new approach. Psychophysiology 1973; 10: 431–6PubMedCrossRefGoogle Scholar
  41. 41.
    McNair DM, Lorr M, Droppleman LF EITS manual for the profile of mood states. San Diego: Educational and Industrial Testing Service, 1971Google Scholar
  42. 42.
    Atkinson G. Effects of age on human circadian rhythms in physiological and performance measures [thesis]. Liverpool: John Moores University, 1994Google Scholar
  43. 43.
    Atkinson G, Coldwells A, Reilly T, et al. Circadian rhythmicity in self-chosen work-rate. In: Gutenbrunner C, Hildebrandt G, Moog R, editors. Chronobiology and chronomedicine. Basic research and applications. Frankfurt am Main: Peter Lang-Verlag, 1993; 478–84Google Scholar
  44. 44.
    Atkinson G, Coldwells A, Reilly T, et al. The influence of age on diurnal variations in competitive cycling performances. J Sports Sci 1994; 12: 127–8CrossRefGoogle Scholar
  45. 45.
    Conroy RTWL, O’Brien M. Diurnal variation in athletic performance. J Physiol 1974; 236: 51Google Scholar
  46. 46.
    Monk TH. Chronobiology of mental performance. In: Touitou Y, Haus E, editors. Biological rhythms in clinical and laboratory medicine. Berlin: Springer-Verlag, 1992; 208–13CrossRefGoogle Scholar
  47. 47.
    Reilly T, Down A. Circadian variation in the standing broad jump. Percept Mot Skills 1986; 62: 830CrossRefGoogle Scholar
  48. 48.
    Folkard S, Monk TH. Circadian rhythms in human memory. Br J Psychol 1980; 71: 295–307CrossRefGoogle Scholar
  49. 49.
    Harma MI, Ilmarinen J, Yletyinen I. Circadian variation of physiological functions in physically average and very fit dayworkers. J Human Ergol 1982; 11 Suppl.: 33–46Google Scholar
  50. 50.
    Nelson W, Tong TL, Lee J-K, et al. Methods for cosinor rhythmometry. Chronobiologia 1979; 6: 305–23PubMedGoogle Scholar
  51. 51.
    Kleitman N. Sleep and wakefulness. Chigaco: University of Chicago Press, 1963Google Scholar
  52. 52.
    Winget CM, DeRoshia CW, Holley DC. Circadian rhythms and athletic performance. Med Sci Sports Exerc 1985; 17: 498–516PubMedGoogle Scholar
  53. 53.
    Monk TH, Leng VC. Time of day effects in simple repetitive tasks: some possible mechanisms. Acta Psychol (Amst) 1982; 51: 207–21CrossRefGoogle Scholar
  54. 54.
    Gifford LS. Circadian variation in human flexibility and grip strength. Aust J Physiotherapy 1987; 33: 3–9Google Scholar
  55. 55.
    Wright V, Dawson D, Longfield MD. Joint stiffness its characterisation and significance. Biol Med Eng 1969; 4: 8–14Google Scholar
  56. 56.
    Reinberg A, Motohashi Y, Bourdeleau P, et al. Alteration of period and amplitude of circadian rhythms in shift workers. Eur J Appl Physiol 1988; 57: 15–25CrossRefGoogle Scholar
  57. 57.
    Reilly T, Walsh T. Physiological, psychological and performance measures during an endurance record for 5-a-side soccer play. Br J Sports Med 1981; 15: 122–8PubMedCrossRefGoogle Scholar
  58. 58.
    Harkness JA, Richter MB, Panagi GS, et al. Circadian variation in disease activity in rheumatoid athritis. BMJ 1982; 284: 551–5PubMedCrossRefGoogle Scholar
  59. 59.
    Wit A. Zagadnienia regulacji w procesie rozwoju sily miesnionej na przykladzie zawodnikow uprawiajacych podnoszenie ciezarow [in Polish]. Warsaw: Institute of Sport, 1980Google Scholar
  60. 60.
    Wright V, Dawson D, Longfield MD. Joint stiffness — its characterisation and significance. Biol Med Eng 1969; 4: 8–10Google Scholar
  61. 61.
    Freivalds A, Chaffin DB, Langolf GD. Quantification of human performance rhythms. Am Ind Hyg Assoc J 1983; 44: 643–8PubMedCrossRefGoogle Scholar
  62. 62.
    Coldwells A, Atkinson G, Reilly T. Sources of variation in back and leg dynamometry. Ergonomics 1993; 37: 79–86CrossRefGoogle Scholar
  63. 63.
    Atkinson G, Greeves J, Cable T, et al. Day-to-day and circadian variability of leg strength measured with the LIDO isokinetic dynamometer. J Sports Sci 1995; 13: 18–19Google Scholar
  64. 64.
    Cabri J, Clarys JP, De Witte B, et al. Circadian variation in blood pressure responses to muscular exercise. Ergonomics 1988; 31: 1559–66PubMedCrossRefGoogle Scholar
  65. 65.
    Ishee JH, Titlow LW. Diumal variations in physical performance. Percept Mot Skills 1986; 63: 835–8CrossRefGoogle Scholar
  66. 66.
    Hill DW, Smith JC. Circadian rhythm in anaerobic power and capacity. Can J Sports Sci 1991; 16: 30–2Google Scholar
  67. 67.
    Down A, Reilly T, Parry-Billings M. Time of day and performance of the Wingate Anaerobic Test. J Sports Sci 1985; 3: 214Google Scholar
  68. 68.
    Reilly T, Down A. Time of day and performance on all-out arm ergometry. In: Reilly T, Watkins J, Borms J, editors. Kinanthropometry Ill. London: E and FN Spon, 1986; 296–300Google Scholar
  69. 69.
    Lakomy HKA. An ergometer for measuring the power generated during sprinting. J Physiol 1984; 319: 33Google Scholar
  70. 70.
    Hill DW, Borden DO, Darnaby KM, et al. Effect of time of day on aerobic and anaerobic responses to high intensity exercise. Can J Sports Sci 1992; 17: 316–9Google Scholar
  71. 71.
    Reilly T, Baxter C. Influence of time of day on reactions to cycling at a fixed high intensity. Br J Sports Med 1983; 17: 128–30PubMedCrossRefGoogle Scholar
  72. 72.
    Reilly T, Down A. Investigation of circadian rhythms in anaerobic power and capacity of the legs. J Sports Med Phys Fitness 1992; 33: 343–7Google Scholar
  73. 73.
    Reilly T, Marshall S. Circadian rhythms in power output on a swim bench. J Swim Res 1991; 7: 11–13Google Scholar
  74. 74.
    Sinnerton S, Reilly T. Effects of sleep loss and time of day in swimmers. In: Maclaren D, Reilly T, Lees A, editors. Biomechanics and medicine in swimming: swimming science VI. London: E and FN Spon, 1992: 399–405Google Scholar
  75. 75.
    Reilly T, Brooks GA. Exercise and the circadian variation in body temperature measures. Int J Sports Med 1986; 7: 358–62PubMedCrossRefGoogle Scholar
  76. 76.
    Wahlberg I, Astrand I. Physical work capacity during the day and at night. Work Environ Health 1973; 10: 65–8Google Scholar
  77. 77.
    Cohen CJ, Muehl GE. Human circadian rhythms in resting and exercise pulse rates. Ergonomics 1977; 20: 475–9PubMedCrossRefGoogle Scholar
  78. 78.
    Cohen CJ. Human circadian rhythms in heart rate response to a maximal exercise stress. Ergonomics 1980; 23: 591–5PubMedCrossRefGoogle Scholar
  79. 79.
    Reilly T, Robinson G, Minors DS. Some circulatory responses to exercise at different times of day. Med Sci Sports Exerc 1984; 16: 477–82PubMedCrossRefGoogle Scholar
  80. 80.
    Davies CTM, Sargeant AJ. Circadian variation in physiological responses to exercise on a stationary bicycle ergometer. Br J Ind Med 1975; 32: 110–4PubMedGoogle Scholar
  81. 81.
    Home JA, Pettit AN. Sleep deprivation and the physiological responses to exercise under steady state conditions in untrained subjects. Sleep 1984; 7: 168–79Google Scholar
  82. 82.
    Reilly T. Circadian variation in ventilatory and metabolic adaptations to submaximal exercise. Br J Sports Med 1982; 16: 115–9CrossRefGoogle Scholar
  83. 83.
    Reilly T, Brooks GA. Investigation of circadian rhythms in metabolic responses to exercise. Ergonomics 1982; 25: 1093–7PubMedCrossRefGoogle Scholar
  84. 84.
    Faria IE, Drummond BJ. Circadian changes in resting heart rate and body temperature, maximal oxygen consumption and perceived exertion. Ergonomics 1982; 25: 381–6PubMedCrossRefGoogle Scholar
  85. 85.
    Reilly T, Young K. Digit summation, perceived exertion and time of day under submaximal exercise conditions. In: Proceedings of the 20th Intemational Congress of Applied Psychology; 1982 Jul 25–31: Edinburgh. Aston: Intemational Association of Applied Physiology, 1982: 344Google Scholar
  86. 86.
    Reilly T, Tyrrell A, Troup JDG. Circadian variation in human stature, Chronobiol Int 1984; 1: 121–6PubMedCrossRefGoogle Scholar
  87. 87.
    Wilby J, Linge K, Reilly T, et al. Spinal shrinkage in females: circadian variation and the effects of circuit weight-training. Ergonomics 1987; 30: 47–54PubMedCrossRefGoogle Scholar
  88. 88.
    Hessemer V, Langusch D, Bruck K, et al. Effects of slightly lowered body temperature on endurance performance in humans. J Appl Physiol 1984; 57: 1731–7PubMedGoogle Scholar
  89. 89.
    Atkinson G, Reilly T. Effects of age and time of day on preferred work-rates during prolonged exercise. Chronobiol Int 1995; 12: 121–9PubMedCrossRefGoogle Scholar
  90. 90.
    Åstrand P-O, Ryhming I. A nomogram for calculation of aerobic capacity physical fitness from pulse rate during sub-maximal work. J Appl Physiol 1954; 7: 218–21PubMedGoogle Scholar
  91. 91.
    Watson AWS, O’Donovan DJ. The reliability of measurement of PWC 170. Ir J Med Sci 1976; 145: 308CrossRefGoogle Scholar
  92. 92.
    Reilly T. Assessment of some aspects of physical fitness. Appl Ergon 1991; 22: 291–4PubMedCrossRefGoogle Scholar
  93. 93.
    Coldwells A, Atkinson G, Reilly T, et al. Self-chosen work-rate determines day-night differences in work capacity Ergonomics 1993; 36: 313CrossRefGoogle Scholar
  94. 94.
    Torii J, Shinkai S, Hino S, et al. Effect of time of day on adaptive response to a 4-week aerobic exercise program. J Sports Med Phys Fitness 992; 32: 348–52Google Scholar
  95. 95.
    Hill DW, Cureton KJ, Collins MA. Circadian specificity in exercise training. Ergonomics 1989; 32: 79–92PubMedCrossRefGoogle Scholar
  96. 96.
    Hildebrandt G, Gutenbrunner C, Reinhart C, et al. Circadian variation of isometric strength training in man. In: Morgan E, editor. Chronobiology and chronomedicine. Vol. II. Frankfurt: Peter Lang, 1990: 322–9Google Scholar
  97. 97.
    Gutenbrunner C. Circadian variations in physical training. In: Gutenbruner C, Hildebrandt G, Moog R, editors. Chronobiology and chronomedicine. Frankfurt: Peter Lang, 1993: 665–80Google Scholar
  98. 98.
    Hildebrandt G, Strempel H. Chronobiological problems of performance and adaptational capacity. Chronobiologia 1974; 4: 103–5Google Scholar
  99. 99.
    Willich SN, Lewis M, Lowel H, et al. Physical exertion as a trigger of acute myocardial infarction. N Engl J Med 1993; 329: 1684–90PubMedCrossRefGoogle Scholar
  100. 100.
    Duda M. Should CHD patients avoid morning exercise? Physician Sports Med 1987; 15 (Pt 4): 39–42Google Scholar
  101. 101.
    Young BM. The shift towards shiftwork. New Society 1982; 61: 96–7Google Scholar
  102. 102.
    Homberger S, Knauth P. Interindividual differences in the subjective valuation of leisure time utility. Ergonomics 1993; 36: 255–64CrossRefGoogle Scholar
  103. 103.
    Herbert A. The influence of shift-work on leisure activities. A study with repeated measurement. Ergonomics 1983; 26: 565–74PubMedCrossRefGoogle Scholar
  104. 104.
    Frese M, Okenek K. Reasons to leave shift-work and psychological and psychosomatic complaints of former shift-workers. J Appl Physiol 1984; 69: 509–14Google Scholar
  105. 105.
    Monk TH, Folkard S. Making shiftwork tolerable. Basingstoke: Taylor and Francis, 1992Google Scholar
  106. 106.
    Wedderbum A, Scholarios D. Guidelines for shift-workers: trials and errors? Ergonomics 1993; 36: 211–8CrossRefGoogle Scholar
  107. 107.
    Loat CER, Rhodes EC. Jet-lag and human performance. Sports Med 1989; 8: 226–38PubMedCrossRefGoogle Scholar
  108. 108.
    O’Connor PJ, Morgan WP. Athletic performance following rapid traversal of multiple time zones. Sports Med 1990; 10: 20–30PubMedCrossRefGoogle Scholar
  109. 109.
    O’Connor PJ, Morgan WP, Koltyn KF, et al. Air travel across four time zones in college swimmers. J Appl Physiol 1991; 70: 756–63PubMedGoogle Scholar
  110. 110.
    Jehue R, Street D, Huizenga R. Effect of time zone and game time changes on team performance: National Football League. Med Sci Sports Exerc 1993; 25: 127–31PubMedCrossRefGoogle Scholar
  111. 111.
    Reilly T, Maskell P Effects of altering the sleep-wake cycle in human circadian rhythms and motor performance. Proceedings of the First IOC Congress on Sport Science Colorado Springs; 1989: 106Google Scholar
  112. 112.
    Home JA, Ostberg O. Individual differences in human circadian rhythms. Biol Psychol 1977; 5: 179–90CrossRefGoogle Scholar
  113. 113.
    Hill DW, Cureton KJ, Collins MA, et al. Diumal variations in responses to exercise of ‘moming types’ and ‘evening types’. J Sports Med Phys Fitness 1988; 28: 213–9PubMedGoogle Scholar
  114. 114.
    Burgoon PW, Holland GJ, Loy SF, et al. A comparison of morning and evening ‘types’ during maximum exercise. J Appl Sports Sci Res 1992; 6: 115–9Google Scholar
  115. 115.
    Rossi B, Zani A, Mecacci L. Diumal individual differences and performance levels in some sports activities. Percept Mot Skills 1983; 57: 27–30CrossRefGoogle Scholar
  116. 116.
    Christie MJ, McBreaty E. Deep body temperature: diumal variation, sex and personality. J Psychosom Res 1977; 21: 207PubMedCrossRefGoogle Scholar
  117. 117.
    Winget CM, DeRoshia CW, Vemikos-Danellis J, et al. Comparison of circadian rhythms in male and female humans. Waking Sleeping 1977; 1: 359–63Google Scholar
  118. 118.
    Mellette HC, Hutt BK, Askovich SI, et al. Diurnal variations in body temperature. J Appl Physiol 1951; 3: 665–70PubMedGoogle Scholar
  119. 119.
    Atkinson G, Coldwells A, Reilly T, et al. A comparison of circadian rhythms in work performance between physically active and inactive subjects. Ergonomics 1993; 36: 273–81PubMedCrossRefGoogle Scholar
  120. 120.
    Mermin J, Czeisler C. Comparison of ambulatory temperature recordings at varying levels of physical exertion: average amplitude is unchanged by strenuous exercise. Sleep Res 1987; 16: 253Google Scholar
  121. 121.
    Brock MA. Chronobiology and aging. J Am Geriatr Soc 1991; 39: 74–9PubMedGoogle Scholar
  122. 122.
    Leiberman HR, Wurtman JJ, Teicher MH. Circadian rhythms of activity in healthy young and elderly humans. Neurobiol Aging 1989; 10: 259–65CrossRefGoogle Scholar

Copyright information

© Adis International Limited 1996

Authors and Affiliations

  • Greg Atkinson
    • 1
  • Thomas Reilly
    • 1
  1. 1.Centre for Sport and Exercise Sciences, School of Human SciencesLiverpool John Moores UniversityLiverpoolEngland, UK

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