Exercise induced increases in muscle fiber number

  title={Exercise induced increases in muscle fiber number},
  author={William J. Gonyea and Digby G. Sale and Francine B. Gonyea and Alan E. Mikesky},
  journal={European Journal of Applied Physiology and Occupational Physiology},
SummaryThe effect of weight-lifting, which induced muscular enlargement, on fiber number was tested in the flexor carpi radialis muscle by operantly conditioning 6 cats to flex their right wrist against increasing resistance for an average of 101 weeks. The left was used as a control. At the end of training, the cats were performing “one-arm“ lifts with an average of 57% of their body weight. There was an 11% greater muscle weight (P<0.01) and 9% (P<0.02) more fibers in the exercised muscles… 

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Muscle hypertrophy in bodybuilders

  • P. TeschL. Larsson
  • Medicine
    European Journal of Applied Physiology and Occupational Physiology
  • 2004
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