Volitional weight-lifting in rats promotes adaptation via performance and muscle morphology prior to gains in muscle mass

Details

• Personal Author:
  Baker BA ; Chetlin RD ; Miller, G. Roger ; Rader EP ; Wirth, Oliver
• Description:
  Investigation of volitional animal models of resistance training has been instrumental in our understanding of adaptive training. However, these studies have lacked reactive force measurements, a precise performance measure, and morphological analysis at a distinct phase of training - when initial strength gains precede muscle hypertrophy. Our aim was to expose rats to one month of training (70 or 700 g load) on a custom-designed weight-lifting apparatus for analysis of reactive forces and muscle morphology prior to muscle hypertrophy. Exclusively following 700 g load training, forces increased by 21% whereas muscle masses remained unaltered. For soleus (SOL) and tibialis anterior (TA) muscles, 700 g load training increased muscle fiber number per unit area by -20% and decreased muscle fiber area by -20%. Additionally, number of muscle fibers per section increased by 18% for SOL muscles. These results establish that distinct morphological alterations accompany early strength gains in a volitional animal model of load-dependent adaptive resistance training. [Description provided by NIOSH]
• Subjects:
  Animals Musculoskeletal System Occupational Health Safety Staff Development
• Keywords:
  Author Keywords: Operant Conditioning Fiber Cross-sectional Area Fiber Number Force Measurement-equipment Models Morphology Muscle-function Muscles Resistance Exercise Stereology Training Weight-factors

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• ISSN:
  1178-6302
• Document Type:
  Text
• Genre:
  Journal Article
• Place as Subject:
  OSHA Region 3 ; West Virginia
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Division:
  HELD - Health Effects Laboratory Division
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Pages in Document:
  1-9
• Volume:
  8
• NIOSHTIC Number:
  nn:20045192
• Citation:
  Environ Health Insights 2014 Oct; 8(Suppl 1):1-9
• Contact Point Address:
  Erik P. Rader, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, Morgantown, WV, USA
• Email:
  WLZ4@cdc.gov
• Federal Fiscal Year:
  2015
• Peer Reviewed:
  True
• Source Full Name:
  Environmental Health Insights
• Supplement:
  1
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:3ede692f20d4d4b2106fb61125267613cd8a99fcad08342127e24ab8e367a373756eb306c56bd919c6d272f9328ce58b22ae1a3bd599f63c23a7dd0f2ebf6ad7
• Download URL:
  https://stacks.cdc.gov/view/cdc/200705/cdc_200705_DS1.pdf
• File Type:
  [PDF - 1.69 MB ]