Pflügers Archiv

, Volume 381, Issue 2, pp 119–126 | Cite as

Influence of physical workload on freerunning circadian rhythms of man

  • Rütger A. Wever
Heart, Circulation, Respiration and Blood; Environmental and Exercise Physiology


While living under constant conditions and complete isolation from environmental time cues for about 4 weeks, 9 male subjects exercised on a bicycle ergometer seven times per ‘day’ during two weeks and refrained from physical activities during the other 2 weeks. The freerunning circadian rhythms of wakefulness and sleep and of rectal temperature showed, on the average, no difference between the two sections with regard to the autonomous period and the tendency towards internal desynchronization. Even in the one experiment in which the two rhythms became internally desynchronized, the periods of the rhythms remained unchanged during the time the subject worked on the bicycle. Only in one out of the nine subjects, the autonomous period was considerably longer under the influence of work than without it. The hypothesis is advanced that the period of an autonomous rhythm becomes normally independent of physical workload by way of a compensation mechanism.

Key words

Human circadian rhythms Physical workload Internal desynchronization Compensation mechanism 


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  1. Aschoff, J., Wever, R.: Spontanperiodik des Menschen bei Ausschluß aller Zeitgeber. Naturwissenschaften49, 337–342 (1962)Google Scholar
  2. Aschoff, J., Gerecke, U., Wever, R.: Desynchronization of human circadian rhythms. Jap. J. Physiol.17, 450–457 (1967)Google Scholar
  3. Webb, W. B., Agnew, H. W., Jr.: Sleep and waking in a time-free environment. Aerospace Med.45, 617–622 (1974)Google Scholar
  4. Wever, R.: Autonome circadiane Periodik des Menschen unter dem Einfluß verschiedener Beleuchtungs-Bedingungen. Pflügers Arch.306, 71–91 (1969)Google Scholar
  5. Wever, R.: Die ciracadiane Periodik des Menschen als Indikator für die biologische Wirkung elektromagnetischer Felder. Z. Physik. Med.2, 438–471 (1971)Google Scholar
  6. Wever, R.: Internal phase-angle differences in human circadian rhythms: Causes for changes and problems of determinations. Int. J. Chronobiol.1, 371–390 (1973a)Google Scholar
  7. Wever, R.: Der Einfluß des Lichtes auf die circadiane Periodik des Menschen. I. Einfluß auf die autonome Periodik. Z. Physik. Med.3, 121–134 (1973b)Google Scholar
  8. Wever, R.: The influence of self-controlled changes in ambient temperature on autonomous circadian rhythms in man. Pflügers Arch.352, 257–266 (1974a)Google Scholar
  9. Wever, R.: ELF-effects on human circadian rhythms. In: ELF and VLF electromagnetic field effects (M. A. Persinger, ed.), pp. 101–144. New York and London: Plenum Press 1974bGoogle Scholar
  10. Wever, R.: The circadian multi-oscillator system of man. Int. J. Chronobiol.3, 19–55 (1975a)Google Scholar
  11. Wever, R.: Autonomous circadian rhythms in man: Singly versus collectively isolated subjects. Naturwissenschaften62, 443–444 (1975b)Google Scholar
  12. Wever, R.: The circadian system of man. New York, Heidelberg, Berlin: Springer 1979aGoogle Scholar
  13. Wever, R.: Phase shifts of human circadian rhythms due to shifts of artificial zeitgebers. Chronobiologia (in press, 1979b)Google Scholar

Copyright information

© Springer-Verlag 1979

Authors and Affiliations

  • Rütger A. Wever
    • 1
  1. 1.Max-Planck-Institut für VerhaltensphysiologieAndechsFederal Republic of Germany

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