Research

Mixed

When eccentric and concentric resistance training are matched for maximum load or total work, they produce similar increases in whole muscle size (hypertrophy), despite inducing distinct structural adaptations.

If your goal is maximum muscle size, you do not need to prioritize eccentric-only training. As long as you match the total work or the load used in concentric training, eccentric training will build similar muscle mass. However, expect different structural changes: eccentric training tends to increase fascicle length (muscle belly length), while concentric training tends to increase pennation angle (fiber packing density). For general hypertrophy, either mode works if the stimulus is matched.

GoodQualifiesHIGH confidence
We conclude that, when matched for either maximum load or work, similar increase in muscle size is found between ECC and CON RT. However, such hypertrophic changes appear to be achieved through distinct structural adaptations, which may be regulated by different myogenic and molecular responses observed between lengthening and shortening contractions.
Martino V. Franchi et al. · Frontiers in Physiology · 2017

Why this rating

The conclusion is based on a comprehensive review of multiple human studies comparing ECC and CON, though individual study results vary.

Source

Skeletal Muscle Remodeling in Response to Eccentric vs. Concentric Loading: Morphological, Molecular, and Metabolic Adaptations

Martino V. Franchi et al. · Frontiers in Physiology · 2017

DOI 10.3389/fphys.2017.00447

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DOI resolved against Crossref · corpus check 2026-06-10

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