Skeletal Muscle Remodeling in Response to Eccentric vs. Concentric Loading: Morphological, Molecular, and Metabolic Adaptations.
Level 5 - mechanism / opinion, no new human data
Narrative review of existing literature without systematic methodology.
PubMed 28725197 · doi:10.3389/fphys.2017.00447
What was done
This narrative review critically synthesized literature comparing eccentric versus concentric resistance training regarding muscle hypertrophy, architectural remodeling, muscle protein synthesis, and underlying myogenic molecular mechanisms.
What was found
The abstract reports no numerical values or statistical effect sizes. It notes that active muscle lengthening generates greater force at a lower metabolic cost than shortening. When matched for either maximum load or work, eccentric and concentric resistance training produce similar increases in overall muscle size. However, this growth is achieved through distinct adaptations in muscle architecture despite similar acute and chronic muscle protein synthesis responses.
Why it matters
It clarifies that contraction mode alters the specific structural pathways of muscle remodeling even when net hypertrophic gains are comparable under matched conditions.
Limits
The paper is a narrative review with no systematic search criteria, meta-analysis, or risk-of-bias assessment reported. The abstract provides no quantitative metrics, participant sample sizes, or demographic details.
Cited by
- supports Eccentric and concentric exercises have different intracellular signaling cascades, implying a synergism for muscle hypertrophy.
- supports Muscles develop regionally, with eccentric exercise promoting growth more in the distal portion and concentric exercise promoting growth more in the mid-portion.