The Claim

In male bodybuilders, rectus femoris muscle stiffness does not significantly differ across regions when knee flexion angle is altered between 60° and 90° under isometric conditions with constant hip angle, indicating that hip position has a greater influence on rectus femoris mechanical behavior than knee angle.

Source: Effects of knee and hip flexion angle on region-specific and longitudinal compartmental muscle stiffness of the rectus femoris using shear wave elastography in male bodybuilders

What the research says

Supports is higher

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

Supports
40score
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

For male bodybuilders, changing the knee bend doesn't really affect a key thigh muscle's stiffness if the hip stays in the same position — but changing the hip position does seem to matter more.

See the scientific wording

In male bodybuilders, knee flexion angle alone does not significantly alter rectus femoris muscle stiffness across regions when hip angle is held constant, as no significant differences were reported at 60° or 90° knee flexion across hip angles, suggesting hip position has a stronger influence on rectus femoris mechanical behavior than knee angle under isometric conditions.

What the research says

1 study
  1. Study: Effects of knee and hip flexion angle on region-specific and longitudinal compartmental muscle stiffness of the rectus femoris using shear wave elastography in male bodybuilders

    The study found that changing the hip position affects the rectus femoris muscle more than changing the knee angle, especially when the hip is more extended, which supports the idea that hip position matters more than knee angle for this muscle's stiffness.

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

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