Athletic footwear, leg stiffness, and running kinematics.

摘要: Context The leg acts as a linear spring during running and hopping adapts to the stiffness of surface, maintaining constant total leg-surface system. Introducing substance (eg, footwear) may affect in response changes surface stiffness. Objective To determine if type athletic footwear affects regulation dynamic activities. Design Repeated-measures design. Setting Motion analysis laboratory. Patients or other participants Nine healthy adults (age = 28 +/- 6.8 years, mass 71.6 12.9 kg) free from lower extremity injuries. Intervention(s) Subjects hopped at 2.2 Hz on forceplate under 3 conditions (barefoot, low-cost footwear, high-cost footwear). ran treadmill 2 speeds (2.23 m/s, 3.58 m/s) same conditions. Main outcome measure(s) Limb was calculated data. Kinematic data (knee ankle angles initial contact peak joint excursion after contact) were collected running. We 1-way repeated-measures (stiffness) 2-way (speed by analyses variance (running kinematics) test dependent variables. Results A significant increase barefoot "cushioned" shoe condition noted hopping. When shod, runners landed more dorsiflexion but had less motion than when barefoot. No differences seen between types shoes. primary kinematic difference identified speed increased: knee flexion. At ankle, increased significantly greater extent did shod increased. Conclusions Footwear influences maintenance Differences cushioning properties shoes tested not appear be significant.