Muscle fiber number in the biceps brachii muscle of young and old men

@article{Klein2003MuscleFN,
  title={Muscle fiber number in the biceps brachii muscle of young and old men},
  author={Cliff S Klein and Greg D. Marsh and Robert J. Petrella and Charles L Rice},
  journal={Muscle \& Nerve},
  year={2003},
  volume={28}
}
We have compared the number of muscle fibers in the biceps brachii muscle (BB) of six old men (82.3 ± 4.3 years) and six young men (21.2 ± 1.9 years). Muscle fiber number was estimated by dividing the maximal area of the BB, determined with magnetic resonance imaging, by the mean fiber area of the BB determined in a muscle biopsy. The percentage of type II fibers in the BB (∼60%) and the type I fiber area were not different between the groups. The BB area (−26%), type II fiber area (−24%), mean… 

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