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Updated: Jun 15, 2026

Induction and Assessment of Exertional Skeletal Muscle Damage in Humans

Induction and Assessment of Exertional Skeletal Muscle Damage in Humans

Published on: December 11, 2016

Prolonged muscle damage depends on force variability.

A Skurvydas¹, M Brazaitis, S Kamandulis

¹Lithuanian Academy of Physical Education, Department of Applied Physiology and Physiotherapy, Kaunas, Lithuania.

International Journal of Sports Medicine

|March 12, 2010

Summary

This summary is machine-generated.

Intraindividual variability in eccentric exercise (EE) is closely linked to prolonged skeletal muscle damage. Greater EE variability leads to longer-lasting decreases in muscle force, impacting recovery.

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Area of Science:

Exercise Physiology
Sports Science
Muscle Physiology

Background:

Eccentric exercise (EE) commonly causes skeletal muscle damage.
The link between EE variability and the extent of muscle damage is not well understood.

Purpose of the Study:

To investigate if prolonged reductions in skeletal muscle force after EE are influenced by intraindividual variability.
To test the hypothesis that EE variability affects the duration of exercise-induced muscle damage.

Main Methods:

Eleven healthy men performed maximal intensity knee eccentric extension (10 sets, 12 reps at 160°/s).
Maximal voluntary isometric contraction (MVC) and isokinetic concentric torque (IT) were measured pre- and post-exercise (2 min to 14 days).
Muscle soreness, creatine kinase activity, and EE variability were assessed.

Main Results:

A significant decrease in MVC and IT was observed after EE.
The shift in maximal isokinetic torque occurred at longer muscle lengths post-EE.
Higher intraindividual variability in EE correlated with longer-lasting indirect symptoms of muscle damage.

Conclusions:

Prolonged indirect symptoms of exercise-induced muscle damage, specifically reduced muscle force, are strongly associated with the variability during eccentric exercise.
Understanding EE variability is crucial for predicting and managing muscle recovery.