A thread on the importance of calves outside of jumping & why you should care
Normally, the plantar flexor muscles (calves) “brake” or decelerate ankle dorsiflexion.
If the calves are weak, they are unable to control forward rotation of the leg. The excessive
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Normally, the plantar flexor muscles (calves) “brake” or decelerate ankle dorsiflexion.
If the calves are weak, they are unable to control forward rotation of the leg. The excessive
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dorsiflexed ankle shifts the force of bodyweight backward which creates often unexpected knee flexion torque.
Normally, the soleus muscle should resist this forward motion.
With the foot fixed to the ground, the calves can assist in extending the knee. Because the soleus
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Normally, the soleus muscle should resist this forward motion.
With the foot fixed to the ground, the calves can assist in extending the knee. Because the soleus
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is primarily a slow-twitch muscle, it can produce low force over a long period of time, like in running.
With the foot planted to the ground in stance phase, strong activation of a hip extensor can pull the femur posteriorly (figure B). This helps mechanically lock the
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With the foot planted to the ground in stance phase, strong activation of a hip extensor can pull the femur posteriorly (figure B). This helps mechanically lock the
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knee into extension.
A hip or knee flexion contracture would reduce the effectiveness of this.
While the most important muscles for knee extension are the quads, it helps to have calves that can assist them to help reduce local demands on the quads and
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A hip or knee flexion contracture would reduce the effectiveness of this.
While the most important muscles for knee extension are the quads, it helps to have calves that can assist them to help reduce local demands on the quads and
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reduce forces at the patellafemoral joint, which is often a desired strategy, at least at first, with people who struggle at this.
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