Final answer:
Subtalar pronation during the stance phase decreases rigidity, enables the foot to adapt to uneven terrains, and absorbs shock.
Step-by-step explanation:
During the stance phase, subtalar pronation is the movement of the foot that allows the sole to roll inward. It decreases rigidity, allowing the foot to adapt to uneven terrains and absorb shock. This pronation is important for maintaining balance and stability while walking or running on uneven surfaces, as well as for distributing body weight across the foot. It plays a crucial role in reducing the amount of shock that is passed into the lower limb and body, thus protecting the joints and muscles from excessive strain.