Force training induces changes in human muscle membrane properties
Related Experiment Video
Updated: Mar 22, 2026
Measurement of Maximum Isometric Force Generated by Permeabilized Skeletal Muscle Fibers
Published on: June 16, 2015
Werner J Z'Graggen1,2, Joël P Trautmann2, Hugh Bostock3
1Department of Neurosurgery, Inselspital, Bern University Hospital and University of Bern, Bern, Switzerland.
Introduction:
Human muscle membrane properties can be assessed in vivo by recording muscle velocity recovery cycles (MVRCs). This study was undertaken to study the effect of muscle force training on MVRC parameters.
Methods:
MVRCs with 1 to 5 conditioning stimuli were recorded from brachioradialis muscle before and after 2 weeks of muscle force training in 12 healthy subjects. The effects of training on relative refractory period and early and late supernormality were quantified.
Results:
Force training induced a reduction of relative refractory period (P < 0.0001), while early supernormality was increased (P < 0.02) and peaked earlier (P < 0.01). Late supernormality and the increases in late supernormality due to 2 and 5 conditioning stimuli remained unchanged.
Conclusions:
Muscle force training leads to hyperpolarization of the resting muscle membrane potential, probably caused by an increase in the number of sodium pump sites. Muscle Nerve 54: 144-146, 2016.
More Related Videos
07:55Isolating Myofibrils from Skeletal Muscle Biopsies and Determining Contractile Function with a Nano-Newton Resolution Force Transducer
Published on: May 7, 2020
14:02Ex Vivo Assessment of Contractility, Fatigability and Alternans in Isolated Skeletal Muscles
Published on: November 1, 2012
Related Concept Videos
01:29Relaxation of Skeletal Muscles
When an action potential reaches the axon terminal, it depolarizes the membrane and opens voltage-gated sodium channels. Sodium ions enter the cell, further depolarizing the presynaptic membrane. This depolarization causes voltage-gated calcium channels to open....
01:24Generation of Action Potential in Skeletal Muscles
Like neurons, muscle cells are also regarded as excitable due to their capacity to change in response to stimuli, primarily due to voltage-gated ion channels embedded in their plasma membranes, which get activated by alterations in the...
01:20Motor Unit Stimulation
The latent period of contraction marks the onset of excitation-contraction coupling, when the action potential propagates across the sarcolemma, preparing the muscle fibers for contraction. As the fibers enter the contraction phase, the...
01:27Exercise 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...
01:22Muscle Stimulation Frequency
Wave summation
At low firing rates, motor neurons induce individual twitch contractions in muscle fibers. These twitches...
01:25Smooth Muscle Contraction
The onset of contraction is triggered by an increase in calcium ions within the sarcoplasm, similar to the process in striated muscle. However, smooth muscles have a relatively smaller reservoir of the sarcoplasmic...