The Claim

Eccentric training is associated with greater muscle hypertrophy in upper limb muscles compared to concentric training, based on subgroup analysis of 26 randomized controlled trials (p = 0.018), though the evidence is of very low quality and the finding is exploratory.

Source: Comparison Between Eccentric vs. Concentric Muscle Actions On Hypertrophy: A Systematic Review and Meta-analysis

What the research says

Supports is higher

Support is ahead, but a single strong opposing study can change this.

Supports
39score
Challenges
0score

These are independent scores, not a percentage. Higher-grade studies count more, so a single strong opposing study can outweigh several weaker ones.

Correlation
1 study reviewed
In plain English

Eccentric training is linked to more muscle growth in the upper limbs than concentric training, according to a subgroup analysis of 26 studies, but the evidence supporting this is very weak and was not the main focus of those studies.

See the scientific wording

Eccentric training may be associated with greater muscle hypertrophy in upper limb muscles compared to concentric training, based on subgroup analysis of 26 RCTs (p = 0.018), though this finding is exploratory and supported by very low-quality evidence.

Why this might work

When muscles lengthen under load, they experience higher tension that tears muscle fibers slightly more than when they shorten. This damage activates repair systems that build more muscle protein, making the fibers thicker over time.

Suggested mechanismbased on 1 study

What the research says

1 study
  1. Study: Comparison Between Eccentric vs. Concentric Muscle Actions On Hypertrophy: A Systematic Review and Meta-analysis

    Overall, lifting and lowering weights build similar muscle, but in the arms and shoulders, lowering weights slowly might help a little more—though this result is uncertain and based on weak studies.

Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies

Fit Body Science verdict — we translate health claims into clear verdicts backed by peer-reviewed research.

Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.