During the deceleration phase of gait, which muscular actions occur?

During the deceleration phase of gait, which muscular actions occur?

• A. Isometric gluteal contraction
• B. Concentric of quadriceps and eccentric of hamstrings
• C. Concentric of hamstrings and eccentric of quadriceps
• D. No muscle activity

Answer: (B)

During deceleration of the leg in gait, the knee needs to be controlled as the limb slows and prepares for heel contact. The quadriceps fire concentrically to extend the knee, helping to position the leg for the upcoming step. At the same time, the hamstrings contract eccentrically, lengthening while producing force to slow that knee extension and absorb energy. This coordinated pattern provides smooth, controlled deceleration and proper foot placement. An isometric action of the gluteal group wouldn’t deliver the necessary dynamic control, hiring the hamstrings to shorten while the quadriceps lengthen would move the knee in the opposite direction, and no muscle activity would ignore the essential energy-absorbing control needed in this phase.

During deceleration of the leg in gait, the knee needs to be controlled as the limb slows and prepares for heel contact. The quadriceps fire concentrically to extend the knee, helping to position the leg for the upcoming step. At the same time, the hamstrings contract eccentrically, lengthening while producing force to slow that knee extension and absorb energy. This coordinated pattern provides smooth, controlled deceleration and proper foot placement. An isometric action of the gluteal group wouldn’t deliver the necessary dynamic control, hiring the hamstrings to shorten while the quadriceps lengthen would move the knee in the opposite direction, and no muscle activity would ignore the essential energy-absorbing control needed in this phase.