Neural Adjustment in the Activation of the Lower Leg Muscles through Daily Physical Exercises in Community-Based Elderly Persons

DOI Web Site 48 References
  • Maejima Hiroshi
    Division of Physical Therapy and Occupational Therapy Sciences, Graduate School of Health Sciences, Hiroshima University
  • Murase Azusa
    Koyochuo Hospital
  • Sunahori Hitoshi
    Hiroshima Prefectural Rehabilitation Center
  • Kanetada Yuji
    Hatsudai Rehabilitation Hospital
  • Otani Takuya
    Division of Physical Therapy and Occupational Therapy Sciences, Graduate School of Health Sciences, Hiroshima University
  • Yoshimura Osamu
    Hiroshima City Counseling Center for the Physically Disabled
  • Tobimatsu Yoshiko
    Division of Physical Therapy and Occupational Therapy Sciences, Graduate School of Health Sciences, Hiroshima University

Search this article

Abstract

Reflecting the rapidly aging population, community-based interventions in the form of physical exercise have been introduced to promote the health of elderly persons. Many investigation studies have focused on muscle strength in the lower leg as a potent indicator of the effect of physical exercises. The objective of this study was to assess the effect of long-term daily exercises on neural command in lower leg muscle activations. Twenty-six community-based elderly persons (13 men and 13 women; 69.8 ± 0.5 years old) participated in this study. Daily exercise was comprised of walking for more than 30 min, stretching, muscle strengthening and balance exercise, and was continued for three months. Muscle strength and surface electromyography of the tibia anterior, rectus femoris, and biceps femoris were measured in maximum isometric voluntary contraction both before and after the intervention. The mean frequency of the firing of motor units was calculated based on fast Fourier transformation of the electromyography. As the results of the intervention, muscle strength increased significantly only in biceps femoris, whereas the mean frequency of motor units decreased significantly in every muscle, indicating that motor unit firing in lower frequency efficiently induces the same or greater strength compared with before the intervention. Thus, synchronization of motor units compensates for the lower frequency of motor unit firing to maintain muscular strength. In conclusion, long-term physical exercises in the elderly can modulate the neural adjustment of lower leg muscles to promote efficient output of muscle strength.

Journal

References(48)*help

See more

Keywords

Details 詳細情報について

Report a problem

Back to top