The Claim

Free-weight training and machine-based training are associated with similar changes in muscle power, as indicated by an effect size of -0.049 with a 95% confidence interval ranging from -0.557 to 0.460, suggesting that neither modality has a clear advantage for improving explosive strength.

Source: Machines and free weight exercises: a systematic review and meta-analysis comparing changes in muscle size, strength, and power.

What the research says

Supports is higher

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

Supports
33score
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

Lifting free weights and using weight machines both help you get stronger just about the same amount—neither one is clearly better for boosting your explosive power.

See the scientific wording

Free-weight and machine-based training are associated with similar changes in muscle power (effect size: -0.049; 95% CI: -0.557, 0.460), indicating that neither modality has a clear advantage for improving explosive strength.

What the research says

1 study

  1. Study: Machines and free weight exercises: a systematic review and meta-analysis comparing changes in muscle size, strength, and power.

    The study found that lifting free weights and using machines both improve explosive strength about the same amount — neither is better than the other.

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.