title: Age and sex differences of controlled force exertion measured by a computer-generated quasi-random target-pursuit system.
abstract: OBJECTIVE
  This study examined age and sex differences of controlled force exertion measured by a computer-generated quasi-random target-pursuit system in 207 males and 249 females aged 15 to 86 years.
  
  
  METHODS
  The participants matched submaximal grip exertion of their dominant hand to changing demand values, appearing as a moving quasi-random waveform on the display of a personal computer. They performed the test three times with 1-min intervals (one trial was 40 sec). The total sum of the percent of differences between the demand value and the grip exertion value for 25 sec was used as an evaluation parameter.
  
  
  RESULTS
  The errors in controlled force exertion tended to increase constantly with age in both sexes. Significant linear regressions were identified, but there was no significant difference in the rate of increase in both sexes. Analysis of variance showed nonsignificant sex differences among means, except for those in individuals older than 60 years; significant differences between means in the groups older than the 40 yr.-old age group and the 20-24 yr.-old group were found in both sexes.
  
  
  CONCLUSIONS
  Controlled force exertion did not show a significant sex difference and decreased gradually with age in both sexes, but decreased remarkably after 40 years of age.
authors.affiliation: Kyoto Pharmaceutical University, Department of Health and Sports Sciences, 5 Nakauchi-cho, Misasagi, Yamashina-ku, Kyoto, Kyoto 607-8414 Japan. ynaga@mb.kyoto-phu.ac.jp
authors.forename: Y
authors.initials: Y
authors.lastname: Nagasawa
authors.forename: S
authors.initials: S
authors.lastname: Demura
authors.forename: H
authors.initials: H
authors.lastname: Hamazaki
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D053580:Muscle Strength / Q000502:physiology*; D053581:Muscle Strength Dynamometer / Q000706:statistics & numerical data / Q000639:trends*; D011897:Random Allocation; D012727:Sex Characteristics; D014584:User-Computer Interface; D055815:Young Adult