Eccentric contraction
Eccentric contraction has been studied in 2 papers since 2016: none in people yet, 1 in animals, 1 review. The research so far is in animals. The newest paper, Jun 28, 2020: “Hallmarks of frailty and osteosarcopenia in prematurely aged PolgA(D257A/D257A) mice”.
2 papers study it3 findingsUpdated
None of its findings points the other way.
- 2 independent labs in 2 countries
- Funders: National Health and Medical Research Council and 3 more
- Animals1
What did studies of Eccentric contraction find?
2Studies of Eccentric contraction measured 2 outcomes; the most studied are muscle strength (1 study) and muscle mass (1).
Muscle strength
downin mice1
1 study
Muscle strength
downin mice1
Eccentric contraction impairs muscle strength in mice (∼92% loss of maximum force).
“greatest loss of ∼92% recorded in senescent 22-month-old mdx mice”
Animalsmdx miceextensor digitorum longus
Frontiers in physiology
Muscle mass
no changein mice1
1 study
Muscle mass
no changein mice1
Eccentric contraction has no effect on muscle mass in mice.
“There were no detectable differences in muscle mass or myofibre cross-sectional area despite continued deficits in force following EIMD in either age group.”
Animalsboth age groupsskeletal muscle20 eccentric contractions3 days after injurymales
Functional recovery from eccentric injury is maintained in sarcopenic mouse muscle
JCSM rapid communications
What is Eccentric contraction linked with?
1Studies link Eccentric contraction with 1 measure, most often branched fibers (1 study).
Branched fibers
upin mice1
1 study
Branched fibers
upin mice1
Eccentric contraction is associated with branched fibers in mice.
“correlated with a dramatic increase in the number and complexity of branched fibers”
Animalsmdx miceextensor digitorum longus
Frontiers in physiology