The research, done at a US university, proves that wearing high heels can strengthen the ankle initially, but leads to weakening and instability over time.
With prolonged use you get muscle shortening in the back of the leg and muscle lengthening in the front of the leg. These changes in muscle length then can change muscle strength.
In sneakers or flat shoes, the foot is positioned in neutral where the bones of the ankle are under the bones of the lower leg, creating a more stable joint and a decreased likelihood of injury.
High-heeled shoes also change the normal walking or gait cycle, with the ultimate result being a less fluent gait cycle.
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