The Claim

In resistance-trained men, the rectus femoris muscle exhibits significantly greater electromyographic activation during knee extension exercises compared to leg press exercises, with a mean difference of 24.3%, an effect size of 0.93, and a p-value of 0.002, likely due to the biarticular nature of the rectus femoris being more challenged during isolated knee extension without concurrent hip extension.

Source: Electromyographic Comparison of Five Lower-Limb Muscles between Single- and Multi-Joint Exercises among Trained Men.

What the research says

Supports is higher

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

Supports
34score
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.

How it works
1 study reviewed
In plain English

If you're a guy who lifts weights, your front thigh muscle works way harder during leg extensions than during leg presses — probably because the movement challenges how that muscle crosses two joints at once.

See the scientific wording

In resistance-trained men, the rectus femoris muscle shows significantly higher electromyographic activation during knee extension (mean difference: 24.3%, effect size = 0.93, p = 0.002) compared to leg press, likely due to its biarticular function being more challenged in isolated knee extension without concurrent hip extension.

What the research says

1 study
  1. Study: Electromyographic Comparison of Five Lower-Limb Muscles between Single- and Multi-Joint Exercises among Trained Men.

    The study found that the rectus femoris muscle works harder during knee extension than leg press in trained men, just like the claim says.

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

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