posture
A high heel shoe puts your foot in a plantarflexed (foot pointed downward) position, placing an increased amount of pressure on your forefoot.
This causes you to adjust the rest of your body to maintain your balance. The lower part of your body leans forward and to compensate for that, the upper part of your body must lean back to keep you balanced. This is not your body’s normal standing position.
Gait
When walking, your foot is in a more fixed downward position (plantarflexed) therefore you are not able to push off the ground with as much force. This causes your hip flexor muscles in your legs to work harder to move and pull your body forward. Your knees also stay more bent (flexed) and forward, causing your knee muscles to work harder
Balance
Walking in high heel shoes is like walking on a balance beam. It takes a lot of balance and just like teetering on a beam, there is not any support in a high heel shoe to catch you if you fall. High heel shoes cause your foot and ankle to move in a supinated (turned outward) position. This position puts you at risk for losing your balance and spraining your ankles.