In untrained young men, performing leg extensions with the hip bent to 40 degrees results in greater growth of the rectus femoris muscle than bending the hip to 90 degrees, while 90-degree hip...
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In untrained young men, performing leg extensions with the hip bent to 40 degrees results in greater growth of the rectus femoris muscle than bending the hip to 90 degrees, while 90-degree hip...
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Training with 40° hip flexion during leg extensions preferentially increases rectus femoris hypertrophy compared to 90° hip flexion in untrained young men, while 90° hip flexion produces equivalent overall quadriceps hypertrophy without selective bias.
When the hip is bent less during leg extensions, the rectus femoris muscle is stretched more at the start of the movement. This stretch increases the force the muscle experiences during contraction, which triggers more muscle growth in that specific muscle. The other muscles in the thigh grow similarly regardless of hip angle because they are not affected by hip position.
What the research says
Supports
1 study
Study: The effects of hip flexion angle on quadriceps femoris muscle hypertrophy in the leg extension exercise
This study provides evidence supporting the claim.
Contradicts
0 studies
Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies