Related Experiment Video

Updated: Mar 10, 2026

Isokinetic Robotic Device to Improve Test-Retest and Inter-Rater Reliability for Stretch Reflex Measurements in Stroke Patients with Spasticity

Isokinetic Robotic Device to Improve Test-Retest and Inter-Rater Reliability for Stretch Reflex Measurements in Stroke Patients with Spasticity

Published on: June 12, 2019

Intersession reliability of the interpolated twitch technique applied during isometric, concentric, and eccentric

Martin Behrens¹, Florian Husmann¹, Martin Gube¹

¹Institute of Sport Science, University of Rostock, Ulmenstraße 69, 18057, Rostock, Germany.

|December 10, 2016

Abstract

Introduction:

Although it has been shown that voluntary activation (%VA) of the knee extensors during isometric contractions can be reliably assessed with the interpolated twitch technique, little is known about the reliability of %VA during concentric and eccentric muscle actions. Therefore, relative and absolute intersession reliability of quadriceps muscle's %VA during different contraction modes was determined.

Methods:

After a familiarization session, 21 participants (17 males, 25 ± 2 yrs) completed two testing sessions. Paired supramaximal electrical stimuli were administered to the femoral nerve during isometric, concentric, eccentric MVCs, and at rest to assess %VA (stimuli were applied at 70° knee flexion).

Results And Discussion:

Data indicate that %VA of the knee extensors can be reliably measured during isometric [intraclass correlation coefficient (ICC) = 0.89, coefficient of variation (CV) = 4.1%], concentric (ICC = 0.87, CV = 6.6%), and eccentric muscle actions (ICC = 0.86, CV = 7.0%). Muscle Nerve 56: 324-327, 2017.

Keywords:

electrical stimulation femoral nerve paired electrical stimuli quadriceps femoris muscle twitch voluntary activation

More Related Videos

In Vivo Canine Muscle Function Assay

In Vivo Canine Muscle Function Assay

Published on: April 5, 2011

In vivo Measurement of Knee Extensor Muscle Function in Mice

In vivo Measurement of Knee Extensor Muscle Function in Mice

Published on: March 4, 2021

Related Concept Videos

Muscle Stimulation Frequency

Muscle Stimulation Frequency

The contraction strength of muscles is regulated by motor neurons, which modulate the frequency of action potentials dispatched to the motor units based on the body's requirements. This process of varying the muscle stimulation frequency allows muscles to contract with a force that is precisely tailored to the needs of the moment, whether lifting a feather or a heavy box.
Wave summation
At low firing rates, motor neurons induce individual twitch contractions in muscle fibers. These twitches...

Isotonic and Isometric Muscle Contractions

Isotonic and Isometric Muscle Contractions

Two primary types of muscle contractions are isotonic and isometric, each serving unique functions and involving distinct mechanisms. Both isotonic and isometric contractions are integral to the body's complex system of movement and stability. Isotonic exercises contribute significantly to functional strength and movement, while isometric contractions are crucial for maintaining posture and joint stability.
Isotonic contractions
Isotonic contractions occur when a muscle changes length while...

Motor Unit Stimulation

Motor Unit Stimulation

When the neuron of a motor unit fires an action potential, it triggers a series of events, leading to a twitch contraction in the muscle fibers. The process of excitation-contraction coupling is crucial in relaying the action potential to the muscle fibers.
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...

Articles linked to this work by shared authors, journal, and citation graph.

Digitally supported physical cancer rehabilitation during and after systemic treatment in South Baltic countries: Protocol for the AMBeR eRehab feasibility study.

Advances in clinical and experimental medicine : official organ Wroclaw Medical University·2026

Effects of a Multimodal Exercise Intervention on Single- and Dual-Task Gait Performance in Older Patients with Open-Angle Glaucoma: A Pilot Study.

Geriatrics (Basel, Switzerland)·2026

[Use of AI during creation of scientific reviews: the example of sarcopenia in head and neck cancer].

HNO·2026

Does exercising bilaterally require measuring bilaterally? Bilateral versus unilateral tourniquet cuff inflation during measurement of arterial occlusion pressure: considerations for blood flow restriction exercise.

Frontiers in physiology·2026

Moderate-to-good acceptability of smartwatch monitoring in head and neck cancer survivors: findings from the MOVE-1 feasibility study.

Frontiers in oncology·2026

Haematological and Oncological Training Therapy With Stationary Strength and Cardio Machines (HOT) in Routine Cancer Care: A 3-Year Real-World Evaluation of Acceptance, Feasibility, Safety, and Effects.

Cancer medicine·2026

See all related articles