Fatigue and Recovery at Long and Short Muscle Lengths After Eccentric Training

Details

• Personal Author:
  Stauber WT ; Willems MET
• Description:
  To determine the effects of high-speed eccentric training of rat plantar flexor muscles on: 1) maximum (120 Hz) force at 90[degrees] ankle position; 2) fatigue (40 concentric muscle actions, ROM 50[degrees]) and recovery (6 concentric muscle actions) tested at short or long muscle lengths; and 3) low-frequency fatigue. Training consisted of eccentric muscle actions from ankle positions of 140[degrees] to 40[degrees] (velocity approximately 400 degrees [middle dot]s-1) followed by unresisted concentric muscle actions (5 x 10 repetitions, 5 d[middle dot]wk-1 for 6 wk). Fatigue was induced by concentric muscle actions with a rest of 12.5 s between muscle actions, and recovery consisted of equivalent concentric muscle actions performed every 5 min for 30 min. Low-frequency fatigue was measured 35 min after testing at 90[degrees] ankle position by using the ratio of isometric force produced by 20- and 100-Hz stimulation frequencies. Eccentric training increased maximal isometric force per muscle weight by 22% whereas muscle weights were unchanged. In control muscles (C), isometric force immediately preceding each concentric muscle action decreased more at long lengths than at short lengths during the fatigue protocol; this length-dependent difference disappeared after 30 min of recovery. At short lengths, isometric force decreased less in trained muscles (T) (C: 78.4 +/- 3.6%; T: 59.6 +/- 4.4%) and recovered more during the following 30-min period (C: 84.7 +/- 2.5%; T: 95.4 +/- 2.8% of initial values). Changes in F20/F100 were smaller for trained muscles (C: 35.4 +/- 2.0%; T: 22.0 +/- 1.4%). High-speed eccentric training (5 d[middle dot]wk-1 for 6 wk) reduced fatigability and enhanced recovery mainly at long muscle lengths. It also reduced low-frequency fatigue, which may be attributed to alterations in intracellular calcium handling. [Description provided by NIOSH]
• Subjects:
  Animals Fatigue Laboratories Musculoskeletal System Occupational Health Safety
• Keywords:
  Animal Studies Injuries Laboratory Animals Muscles Muscle Tissue Musculoskeletal System Skeletal System
• ISSN:
  0195-9131
• Document Type:
  Text
• Funding:
  Grant
• Genre:
  Journal Article
• Place as Subject:
  OSHA Region 3 ; West Virginia
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Volume:
  34
• Issue:
  11
• NIOSHTIC Number:
  nn:20029540
• Citation:
  Med Sci Sports Exerc 2002 Nov; 34(11):1738-1743
• Contact Point Address:
  Department of Biochemistry, P.O. Box 9142, West Virginia University Health Sciences Center, Morgantown, WV 26506-9142
• Federal Fiscal Year:
  2003
• NORA Priority Area:
  Disease and Injury: Musculoskeletal Disorders of the Upper Extremities
• Performing Organization:
  West Virginia University, Morgantown, West Virginia
• Peer Reviewed:
  True
• Start Date:
  19920101
• Source Full Name:
  Medicine and Science in Sports and Exercise
• End Date:
  20050531
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:4e4aed9780b07e9f15c11d89de0a1a66ad2c6ad721d838ea4f9a86ed47f368b9a1fe5a009b2d35f1b7ccd97fef67eb3e54ad69dbfb4b8697447852ce4886cd92
• Download URL:
  https://stacks.cdc.gov/view/cdc/190495/cdc_190495_DS1.pdf
• File Type:
  [PDF - 169.78 KB ]