Histochemistry and Cell Biology

, Volume 112, Issue 1, pp 73–78

Training affects myosin heavy chain phenotype in the trapezius muscle of women

  • F. Kadi
  • Lars-Eric Thornell
Original Paper

DOI: 10.1007/s004180050393

Cite this article as:
Kadi, F. & Thornell, LE. Histochemistry (1999) 112: 73. doi:10.1007/s004180050393


The aim of this investigation was to determine whether 10 weeks of three different types of training can alter the myosin heavy chain (MyHC) composition of the trapezius muscle. Twenty-one women were randomly assigned to three training groups that performed strength (n=9), endurance (n=7) or coordination training (n=5). Pre and post biopsies were taken from the upper part of the descending trapezius muscle and were analysed for MyHC isoform content using 5% gel electrophoresis. In addition, we have studied the expression of embryonic and neonatal MyHCs using double-immunofluorescence staining. In the strength-trained group, there was a significant increase in the amount of MyHC IIA and a significant decrease in the amount of MyHC IIB and MyHC I. In the endurance group, there was a significant decrease in the amount of MyHC IIB. MyHC composition in the coordination group was not altered. Following the training period, myotubes and individual small-sized muscle fibres were observed in the strength and endurance trained groups. These structures were stained with the markers for early myogenesis (MyHC embryonic and neonatal). These data suggest that specific shifts in MyHC isoforms occur in the trapezius muscle following strength and endurance training. The presence of small-sized muscle fibres expressing the developmental isoforms of MyHC suggests that strength and endurance training induced the formation of new muscle fibres.

Copyright information

© Springer-Verlag Berlin Heidelberg 1999

Authors and Affiliations

  • F. Kadi
    • 1
  • Lars-Eric Thornell
    • 1
  1. 1.Department of Anatomy, Umeå University, S-901 87 Umeå, Sweden e-mail: fawzi.kadi@anatomy.umu.se Tel.: +46-90-786-5122 Fax: +46-90-786-5480SE
  2. 2.URA CNRS 2115, ”Cytosquelette et Développement” F-75013 Paris, FranceFR
  3. 3.Department of Musculoskeletal Research, National Institute for Working Life, Umeå University, S-901 87, Umeå, SwedenSE