Neuromuscular Physiology

Professor Brent Ruby from the Exercise Science Program, Department of Health and Human Performance, The University of Montana, performing a percutaneous (Bergstrom) needle muscle biopsy on a research subject prior to an exercise trial. This method was introduced to applied human physiology in the 1960's, and numerous U.S. research scientists at that time, and in the years that followed, completed training in the method.  Such work led to an explosion of exercise physiology-based research during the 1970's and 1980's of the importance of muscle glycogen to exercise performance, dietary methods to optimize muscle glycogen, skeletal muscle histology and fiber type determinations based on staining for the enzyme myosin ATPase, etc. Such work then led to added questions of the influence of different training modes and methods on muscle structure and function, gender differences, the influence of aging, thermal stress, etc. The method is still used today, though subsequent research identifying concerns of sampling errors (a small muscle sample not reflecting true whole muscle characteristics) and the development of alternative non-invasive methods for studying muscle metabolism has diminished the importance of this technique.

Recommended sequence of topics:

Overview of neuromuscular physiology

Excitable membranes

Action potentials


Developing motor patterns within the CNS

The neuromuscular Junction

Motor units

Skeletal muscle anatomy

Contractile proteins and support matrix of skeletal muscle

Muscle contraction

The muscle biopsy procedure

Muscle fiber types

Functional implications of motor unit recruitment

The muscle twitch

Contraction types