U.S. flag An official website of the United States government.
Official websites use .gov

A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS

A lock ( ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.

i

Length-Dependent Fatigue in Rat Plantar Flexor Muscles After Resistance Training



Details

  • Personal Author:
  • Description:
    For plantar flexor muscles, we examined isometric muscle fatigue at two different ankle positions in resistance trained female Sprague Dawley rats. Resistance training consisted of repeated stretch-shorten contractions (5×10 repetitions, 5 d/wk for 6 wks) of maximally active muscles produced by manual ankle rotations between about 140 degrees and 40 degrees. In two groups of rats, muscle fatigue was produced by 40 repeated concentric contractions over two different ranges of ankle motion [40 degrees to 90 degrees (long muscle lengths, n = 5) and 70 degrees to 120 degrees (short muscle lengths, n = 5)] by rotation at 50 os-1 immediately after an isometric preload contraction (duration 1.9 s, rest period 12.5 s). After 30 min of recovery, a single contraction was performed. Isometric forces were measured either at 40 degrees (ISO40 degrees-rats) or 70 degrees (ISO70 degrees-rats). Overall, resistance training increased the isometric force per gram muscle weight by 21%. In ISO70 degrees-rats, declines in force during fatigue were similar for training (60.7 +/- 8.1%, mean +/- SD) and control (67.5 +/- 6.7%). However, in ISO40 degrees-rats, less fatigue was observed after training (59.6 +/- 10.9%) compared to control (78.4 +/- 8.8%, P = 0.02). After recovery for 30 min, the isometric forces expressed as a percentage of initial values were similar in ISO70 degrees-rats for training (79.5 +/- 6.8%) and control (80.3 +/- 4.7%) but in ISO40 degrees-rats they were higher after training (95.4 +/- 6.9%) compared to control (84.7 +/- 6.2%, P = 0.03). Fatigue and recovery from fatigue were improved by resistance training (5d/wk for 6 wks) of rat plantar flexor muscles but only at relatively long muscle lengths. [Description provided by NIOSH]
  • Subjects:
  • Keywords:
  • ISSN:
    0195-9131
  • Document Type:
    Text
  • Funding:
    Grant
  • Genre:
    Abstract or Summary
  • Place as Subject:
  • CIO:
    National Institute for Occupational Safety and Health (NIOSH)
  • Topic:
    Workplace Safety & Health
  • Location:
    North America
  • Volume:
    33
  • Issue:
    5
  • NIOSHTIC Number:
    nn:20029545
  • Citation:
    Med Sci Sports Exerc 2001 May; 33(5)(Suppl 1):S262
  • Federal Fiscal Year:
    2001
  • NORA Priority Area:
    Disease and Injury: Musculoskeletal Disorders of the Upper Extremities
  • Performing Organization:
    West Virginia University, Morgantown, West Virginia
  • Peer Reviewed:
    False
  • Start Date:
    19920101
  • Source Full Name:
    Medicine and Science in Sports and Exercise
  • Supplement:
    1
  • End Date:
    20050531
  • Collection(s):
  • Main Document Checksum:
    urn:sha-512:ff154aa7bf7b7527e4ec9885fe0cbe1205d4b06a8c181bfed8dc16bb208daabda31c6d3f19572108767084fa14f4cbb82999ed08d609a3daccb76700f3eccda6
  • Download URL:
  • File Type:
    Filetype[PDF - 36.99 KB ]
PREVIOUS
ON THIS PAGE
Details
CDC STACKS serves as an archival repository of CDC-published products including scientific findings, journal articles, guidelines, recommendations, or other public health information authored or co-authored by CDC or funded partners.

As a repository, CDC STACKS retains documents in their original published format to ensure public access to scientific information.
BACK TO TOP