title: Circadian Characteristics of Older Adults and Aerobic Capacity.
abstract: Alteration of circadian rhythmicity with aging might depend on physical aerobic capacity.
  
  
  
  Three groups of participants were established based on their peak oxygen consumption (Group 1 < 20mL/min/kg; Group 2 > 20mL/min/kg and <30mL/min/kg; Group 3 > 30mL/min/kg). Each participant had an individual evaluation of their circadian rhythmicity characteristics through two well-known circadian rhythms: core temperature and rest/activity cycles. Nocturnal sleep was also recorded using actimetry and diurnal vigilance tested in a car driving simulator.
  
  
  
  The amplitude of the oral temperature fluctuations for Group 1 is significantly lower (p < .05) than that of Group 3. Group 2 (p < .01) and Group 3 (p < .05) were significantly more active during the day than Group 1. The index of inactivity during the night for Groups 2 (p < .05) and 3 (p < .01) was higher than Group 1. Results of the car driving simulation showed that for Group 1, the number of lane crossings was significantly higher than Groups 2 (p < .01) and 3 (p < .01). In addition, diurnal vigilance was lower in Group 1.
  
  
  
  The biological clock seems to be enhanced in older participants with a higher level of physical capacity.
authors.affiliation: INSERM, U1075 COMETE, Caen, France.
authors.forename: Sandrine
authors.initials: S
authors.lastname: Dupont Rocher
authors.affiliation: INSERM, U1075 COMETE, Caen, France. Université de Caen Basse-Normandie, U1075 COMETE, France. Bessot-n@phycog.org.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Bessot
authors.affiliation: INSERM, U1075 COMETE, Caen, France. Department of Functional Explorations, CHU de Caen, France.
authors.forename: Bruno
authors.initials: B
authors.lastname: Sesboüé
authors.affiliation: Department of Mathematics, University of Bergen, Norway.
authors.forename: Jan
authors.initials: J
authors.lastname: Bulla
authors.affiliation: INSERM, U1075 COMETE, Caen, France. Université de Caen Basse-Normandie, U1075 COMETE, France.
authors.forename: Damien
authors.initials: D
authors.lastname: Davenne
mesh_terms: D000375:Aging / Q000502:physiology*; D001334:Automobile Driving; D001831:Body Temperature / Q000502:physiology*; D002940:Circadian Rhythm / Q000502:physiology*; D017079:Exercise Tolerance / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010101:Oxygen Consumption / Q000502:physiology
keywords: Exercise; Physical activity; Physical performance