Early events in stretch-induced muscle damage.

  title={Early events in stretch-induced muscle damage.},
  author={David Lewis Morgan and David G Allen},
  journal={Journal of applied physiology},
  volume={87 6},
Unaccustomed exercise involving stretch of active muscle at long length causes an immediate loss of tension-generating capacity, a shift of optimum length, and changes in excitation-contraction coupling. Eventually, fiber damage may be observed, resulting in pain and tenderness. The subject of this review is the early stage in this process, particularly the cause of the immediate drop in tension. There is strong evidence pointing to sarcomere length instabilities and nonuniformities as… 

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Eccentric muscle damage: mechanisms of early reduction of force.

  • D. Allen
  • Biology
    Acta physiologica Scandinavica
  • 2001
Evidence that uncontrolled elongation of some sarcomeres occurs during eccentric contractions on the descending limb leads to the reduced force is considered and the potential of these mechanisms to contribute to the effects of muscle training and to the symptoms of muscle disease, such as muscular dystrophy, is considered.

Muscle damage from eccentric exercise: mechanism, mechanical signs, adaptation and clinical applications

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Stretch speed‐dependent myofiber damage and functional deficits in rat skeletal muscle induced by lengthening contraction

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Exercise-induced muscle damage in humans.

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Pathophysiology of exercise-induced muscle damage and its structural, functional, metabolic, and clinical consequences.

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Dynamic force responses of skeletal muscle during stretch–shortening cycles

The results suggest that muscle damage can be identified by the non-recoverable isometric force decrement and also by the variations in the dynamic force signature during stretch–shortening cycles.

The shift in muscle’s length-tension relation after exercise attributed to increased series compliance

It is concluded that after a series of eccentric contractions of a muscle, the fall in force is the result of a number of interdependent factors, not all of which are a direct consequence of the damage process.

Altering the Length-Tension Relationship with Eccentric Exercise

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Injury to muscle fibres after single stretches of passive and maximally stimulated muscles in mice.

The hypothesis that immediately following a single stretch, the severity of contraction‐induced injury is a function of both strain and average force is tested, and the work done to stretch the muscle was the best predictor of the magnitude of injury.

The effects of repeated active stretches on tension generation and myoplasmic calcium in frog single muscle fibres.

The results exclude reduced myoplasmic [Ca2+] as the cause of the shift in optimum length in this preparation, and both eccentric contractions and twitch potentiation reduced the maximum stimulation rate to which a fibre could respond with propagated action potentials.

Decline running produces more sarcomeres in rat vastus intermedius muscle fibers than does incline running.

A clear and repeatable difference was found, supporting Morgan's prediction of more sarcomeres after decline running, although with some differences in response that depended on the age of the rats.

Excitation failure in eccentric contraction‐induced injury of mouse soleus muscle.

The findings indicate that the force deficit in this muscle injury model results from a failure of the excitation process at some step prior to calcium (Ca2+) release by the sarcoplasmic reticulum.

Sarcomere dynamics and contraction‐induced injury to maximally activated single muscle fibres from soleus muscles of rats.

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Residual force enhancement after stretch of contracting frog single muscle fibers

It is concluded that residual force enhancement after stretch is a property shown by all individual segments along the Fiber of Rana temporaria, a property caused by nonuniformity of sarcomere length along the fiber.

The effect on tension of non‐uniform distribution of length changes applied to frog muscle fibres.

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New insights into the behavior of muscle during active lengthening.

Contraction-induced injury to single fiber segments from fast and slow muscles of rats by single stretches.

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The magnitude of the initial injury induced by stretches of maximally activated muscle fibres of mice and rats increases in old age.

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