Related Experiment Video
Updated: Aug 14, 2026

A Rapid Automated Protocol for Muscle Fiber Population Analysis in Rat Muscle Cross Sections Using Myosin Heavy Chain Immunohistochemistry
Published on: March 28, 2017
Age-related changes in skeletal muscle fiber composition in two swine muscles
1Human Anatomy Section, University of Palermo, Italy.
Abstract:
This study focuses the aging-related modification of skeletal fiber types in two skeletal muscles of different-age swine (6 and 18 month). Rectus abdominis and vastus medialis were employed. It was performed an immunohistochemical staining for slow fibers and it was made a quantitative evaluation, using an automatic interactive image analysis system. The percentage of slow fibers decreased in adult swine. Moreover, slow fibers in rectus abdominis were less numerous than in vastus medialis. Aging and muscle function are two important factors able to modify fiber types. Morphometric analyses can ascertain this modification for diagnostic or nourishmental purposes.
Related Concept Videos
Classification of Skeletal Muscle Fibers
Slow-Twitch Muscle Fibers
Slow oxidative, muscle fibers appear red due to large numbers of capillaries and high levels of...
Types of Skeletal Muscle Fibers
Fast-twitch fibers
Fast-twitch fibers, or Type II fibers, are designed for quick, powerful bursts of speed and strength. They reach peak tension within approximately 0.01 seconds following stimulation. Characterized by a large diameter and densely packed myofibrils, these fibers contain...
Exercise and Muscle Performance
Endurance exercises
Endurance exercises involve running, swimming, or cycling, which require repetitive movements with low force output. When a person engages in endurance exercise, a few noticeable changes occur in their skeletal muscles. For instance, the number of capillaries...

