The down and under stretch primarily stretches which muscle?

The down and under stretch primarily stretches which muscle?

• A. Iliopsoas
• B. Rectus Femoris
• C. Vastus Medialis
• D. Sartorius

Answer: (B)

This stretch targets a muscle that crosses both the hip and the knee, so extending the hip while the knee is positioned to allow liberal lengthening lengthens that muscle the most. The rectus femoris is the only muscle among the options that crosses both joints, making it the primary one lengthened in this position. The other muscles either don’t cross the hip (like the vastus medialis, which only spans the knee) or are primary hip flexors or multi-action muscles whose stretch is not as directly achieved by this specific hip extension/knee position. So the down and under stretch mainly lengthens the rectus femoris.

This stretch targets a muscle that crosses both the hip and the knee, so extending the hip while the knee is positioned to allow liberal lengthening lengthens that muscle the most. The rectus femoris is the only muscle among the options that crosses both joints, making it the primary one lengthened in this position. The other muscles either don’t cross the hip (like the vastus medialis, which only spans the knee) or are primary hip flexors or multi-action muscles whose stretch is not as directly achieved by this specific hip extension/knee position. So the down and under stretch mainly lengthens the rectus femoris.