“Applied Practice 1: Experiencing Tight External Rotators in Forward Bends
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Here’s how it works.……
Try it yourself. Stand in Tadasana on your nonskid mat (Figure 8.14). Step on your right foot, and place your fingers over your right rotators, just posterior to the right greater trochanter. As you feel your left leg lift and swing through, you will feel a strong contraction in the right rotators. Therefore every step you take is one in which the external rotators must contract. This strengthens and tightens the rotators, as do poses in which you stand on one leg or strongly externally rotate, as in many standing poses and back bends.
To understand directly how the rotators interfere with hip flexion, try this. Stand in Tadasana and turn your feet out, contracting the external rotators strongly and pressing your buttocks together. Now hold this position of your femurs and try to bend forward into Uttanasana. It will be very difficult, if not impossible. This is simulating the situation of tight external rotators.
Now internally rotate your femurs. This action is the opposite of external rotation and thus will stretch the external rotators. You will find that bending forward is much easier (Figure 8.15). This is because when stretched, the rotators no longer hold the pelvis back, preventing it from rotating over the femoral heads so that hip flexion can occur. Therefore, to improve your forward bends, stretch not only your hamstrings but also your external rotators.”引自 第八章 盆骨、髋关节和股骨 - 解剖学练习