The Claim

Extending the eccentric phase duration during resistance training is associated with higher levels of muscle damage, as indicated by elevated creatine kinase (CK) levels at 24 and 48 hours post-exercise, and greater increases in anabolic hormones (IGF-1, testosterone, insulin) at 24 hours post-exercise in healthy young men.

Source: Impact of differing eccentric-concentric phase durations on muscle damage and anabolic hormones

What the research says

Supports is higher

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

Supports
31score
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

If you slow down the lowering part of weightlifting, your muscles might get more damaged and your body might release more of the hormones that help build muscle—this is what the claim says about guys who lift weights.

See the scientific wording

Extending the eccentric phase duration during resistance training is associated with higher levels of muscle damage, as indicated by elevated creatine kinase (CK) levels at 24 and 48 hours post-exercise, and greater increases in anabolic hormones (IGF-1, testosterone, insulin) at 24 hours post-exercise in healthy young men.

What the research says

1 study
  1. Study: Impact of differing eccentric-concentric phase durations on muscle damage and anabolic hormones

    The study found that when people slowed down the lowering part of lifts like bench presses and squats, their muscles got more damaged (shown by higher CK levels) and their body released more muscle-building hormones (like testosterone and IGF-1), which matches what the claim says.

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.