Journal ArticleDOI
Fiber type composition of the human female trapezius muscle: enzyme-histochemical characteristics.
TLDR
The differences in fiber type composition between the different parts of the muscle probably reflect different functional demands on the trapezius muscle in various head, neck, and shoulder movements.Abstract:
The human trapezius muscle has an origin that is more extensive than that of any other body muscle; it has a complex macroscopic structure with fibers running in different directions. Histochemical analysis of multiple samples, obtained from different parts of the trapezius muscle from five males, showed marked differences in the distribution and the cross-sectional fiber area of the fiber types among different parts of the muscle as well as among individuals. As revealed by the mATPase activity, after different levels of alkaline and acidic preincubations, the lower third of the descending portion, the transverse, and the ascending portions of the muscle had a predominance of type I fibers (low mATPase activity at pH 9.4), whereas the most superior parts of pars descendens had a higher frequency of type II fibers (high mATPase activity at pH 9.4). The fibers of the most superior parts of the muscle were considerably smaller compared with those in all the other parts. In sections stained for NADH-TR, moth-eaten fibers were observed within parts of the descending portion. Their location and their larger fiber area, compared with that of ordinary type I fibers, may be related to frequent and/or continuous use of these fibers. In conclusion, the differences in fiber type composition between the different parts of the muscle probably reflect different functional demands on the trapezius muscle in various head, neck, and shoulder movements. We suggest that the interindividual differences in muscle fiber composition are due, at least in part, to genetic factors.read more
Citations
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Journal ArticleDOI
Calcium Ion in Skeletal Muscle: Its Crucial Role for Muscle Function, Plasticity, and Disease
TL;DR: Functional alterations of Ca(2+) handling seem to be responsible for the pathophysiological conditions seen in dystrophinopathies, Brody's disease, and malignant hyperthermia, which underline the importance of the affected molecules for correct muscle performance.
Journal ArticleDOI
Pathophysiology of upper extremity muscle disorders
Bart Visser,Jaap H. van Dieën +1 more
TL;DR: There are multiple possible mechanisms, but none of the hypotheses forms a complete explanation and is sufficiently supported by empirical data, according to a review of the literature on the pathophysiology of upper extremity muscle disorders.
Journal ArticleDOI
Gender differences in prevalence of upper extremity musculoskeletal disorders
Delia E. Treaster,Deborah Burr +1 more
TL;DR: It is suggested that women do have significantly higher prevalences than men for many types of UEMSDs, even after controlling for the type of data source and confounders such as age or work factors.
Journal ArticleDOI
Concomitant increases in myonuclear and satellite cell content in female trapezius muscle following strength training
Fawzi Kadi,Lars-Eric Thornell +1 more
TL;DR: The acquisition of additional myonuclei appears to be required to support the enlargement of multinucleated muscle cells following 10 weeks of strength training.
Journal ArticleDOI
Fatty infiltration in the cervical extensor muscles in persistent whiplash-associated disorders: a magnetic resonance imaging analysis.
James M. Elliott,Gwendolen Jull,Jon Timothy Noteboom,Ross Darnell,Graham J. Galloway,Wayne W. Gibbon +5 more
TL;DR: In this paper, a cross-sectional investigation of muscle changes in patients suffering from persistent whiplash-associated disorders (WAD) was conducted, and the muscle changes were found to be associated with muscle atrophy.
References
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Journal ArticleDOI
Muscle Fiber Types: How Many and What Kind?
TL;DR: The purpose of the present communication is to point out some of the problems involved in the classification of fibers and to add new information of value in the analysis of human biopsy material.
Journal ArticleDOI
Data on the distribution of fibre types in thirty-six human muscles: An autopsy study
TL;DR: In this paper, the mean fibre type proportions of each muscle were examined and the spatial distribution of the fibre types was examined in order to determine whether this was random or not, and the number of closed fibers observed in the actual samples was compared statistically with the number expected to occur in a hexagonal lattice model, assuming a random distribution.
Book
Travell & Simons' Myofascial Pain and Dysfunction: The Trigger Point Manual
TL;DR: Lower torso pain and muscle guide hip, thigh and knee pain and muscles guide and muscle leg, ankle and foot pain and Muscle guide.
Journal ArticleDOI
ATPase Activity of Myosin Correlated with Speed of Muscle Shortening
TL;DR: A role for the ATPase activity of myosin in determining the speed of muscle contraction is suggested and the F-actin-binding ability of myOSin from various muscles was rather constant.
Book
Myofascial pain and dysfunction : the trigger point manual
Janet Travell,David G. Simons +1 more
TL;DR: Lower torso pain and muscle guide hip, thigh and knee pain, leg, ankle and foot pain, and muscle guidance lower torso pain, thigh, ankle, foot, and ankle pain this paper.
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