The Claim

Doing leg extensions with your hip bent at 40 degrees instead of 90 degrees probably makes the front thigh muscle (rectus femoris) grow more in guys who haven’t lifted weights before.

Source: The effects of hip flexion angle on quadriceps femoris muscle hypertrophy in the leg extension exercise

What the research says

Supports is higher

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

Supports
54score
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.

Cause and effect
1 study reviewed
In plain English

Doing leg extensions with your hip bent at 40 degrees instead of 90 degrees probably makes the front thigh muscle (rectus femoris) grow more in guys who haven’t lifted weights before.

See the scientific wording

Training the leg extension exercise with 40° hip flexion likely produces greater hypertrophy in the distal and proximal rectus femoris muscle compared to 90° hip flexion in untrained men, based on ultrasound measurements over a 10-week period.

What the research says

1 study

  1. Study: The effects of hip flexion angle on quadriceps femoris muscle hypertrophy in the leg extension exercise

    This study found that doing leg extensions with your hips bent at 40 degrees made the front thigh muscle (rectus femoris) grow more than doing it with hips bent at 90 degrees, and this was true for both the top and bottom parts of the muscle.

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

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