Which of the following is not a fixed support strategy?

• A. Stepping strategy
• B. Ankle strategy
• C. Hip strategy
• D. Ankle strategy and hip strategy together

Answer: (A)

Maintaining balance with fixed-support means keeping the feet planted on the ground while adjusting the body to keep the center of mass over the base of support. The ankle strategy achieves this by small ankle rotations that shift the body's weight without moving the feet. The hip strategy also preserves a fixed base by coordinating larger trunk and hip movements to realign the upper body over the feet. Sometimes both ankle and hip adjustments are used together to counter a perturbation, but the feet remain stationary, so the base of support doesn’t change.

Stepping, on the other hand, changes the base of support by moving a foot to a new position, effectively enlarging or shifting the support area. That’s why stepping is not a fixed-support strategy. It’s employed when disturbances are too large for ankle or hip adjustments alone to keep the body within the current base of support.