Differential Increases in Average Isokinetic Power by Specific Muscle Groups of Older Women Due to Variations in Training and Testing

Details

• Personal Author:
  Asfour SS ; Carmel MP ; Czaja SJ ; Khalil TM ; Ma F ; Morgan RO ; Roos BA ; Signorile JF
• Description:
  Background. As a person ages, leg speed and power decrease. These changes are associated with increased falls and reduced gait speed. It has been shown that upper leg training in younger persons results in increased strength and power at the specific speed at which resistance training is applied, although there are only limited data concerning speed-specific training effects on lower leg activity. However, because both upper and lower leg speed and power influence gait and balance, it is important to determine the training speeds that selectively improve these variables in older persons. Methods. No studies have examined selective speed-specific changes in performance for the upper and lower leg muscles in older individuals. Therefore, we compared shifts in the power-velocity relationship after high-speed (HS) and low-speed (LS) isokinetic training of knee extensors (KE) and flexors (KF), dorsiflexors (DF), and plantar flexors (PF) in community-dwelling women (ages 61 to 75). Subjects were randomly assigned to a HS training, LS training, or control (C) group. Training occurred three times a week for 12 weeks. HS training occurred at 4.73 rad·s-1 (knee) and 3.14 rad·s-1 (ankle); LS training for both joint actions was at 1.05 rad·s-1. Results. HS training improved KE power at intermediate (3.14 rad·s-1; p = .0007) and high (5.24 rad·s-1; p = .0004) testing speeds. Neither the HS nor LS group showed any change in KF as a result of the training. Both LS and HS training improved DF power at all testing speeds; however, PF power improved only with LS training and only at 1.05 rad·s-1 (p = .0132) and 3.14 rad·s-1 (p = .0310). Conclusions. Our results suggest that, in older women, lower leg training should occur at lower training speeds than upper leg training. Additionally, attention to differential speed-specific training of knee and ankle actions could improve power production, mobility, balance, and other functional measures in older persons. [Description provided by NIOSH]
• Subjects:
  Absenteeism Coal Coal Mining Mining Occupational Health Safety
• Keywords:
  Age Factors Biomechanics Lower Extremities Muscle Function Physical Exercise Physiological Testing Women
• ISSN:
  1079-5006
• Document Type:
  Text
• Funding:
  Grant
• Genre:
  Journal Article
• Place as Subject:
  Florida ; OSHA Region 4 ; OSHA Region 6 ; Texas
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Volume:
  57
• Issue:
  10
• NIOSHTIC Number:
  nn:20057525
• Citation:
  J Geront, Ser A Biol Sci Med Sci 2002 Oct; 57(10):M683-M690
• Contact Point Address:
  Joseph F. Signorile, Stein Gerontological Institute, 5200 NE Second Ave., Miami, FL 33137
• Email:
  jsignorile@miami.edu
• Federal Fiscal Year:
  2003
• Performing Organization:
  University of Miami, Coral Gables, Florida
• Peer Reviewed:
  True
• Start Date:
  20010701
• Source Full Name:
  The Journals of Gerontology Series A: Biological Sciences and Medical Sciences
• End Date:
  20040630
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:8bd0fd1ef99264c6b59ed13ecec2657f2f631d2a7580869b5505cda056e677007bd781f93e9f148f57f9d693fc0ed176ab8b167445ed0703316f68e85d6024b4
• Download URL:
  https://stacks.cdc.gov/view/cdc/214854/cdc_214854_DS1.pdf
• File Type:
  [PDF - 140.51 KB ]