Effects of Children's Footwear Midsole Material Hardness On Running Biomechanics

The aim of the study is to get biomechanical parameters of children's shoes with different midsole hardness during running, and to explore the effect of the hardness of children 's shoes on running.It can also provide reference for the design of children's shoes and the selection of children's shoes. Seven children about 3 years old were recruited.Three shoe designs were selected. And two of them were added pad additive (using the shore hardness tester A to measure 55-60A and 75-80A) .The subjects wear the three types of shoes ,respectively, running through the force plate.The results showed that the hip showed significantly less flexed at the initial contact wearing hardness shoes than flexion shoes.The same result was observed for peak flexion angles. The knee showed significantly less peak flexion angles wearing hardness shoes than the other shoes. At the initial contact, the flexion angle of ankle with low hardness is smaller than the other two pairs of shoes. The peak flexion angle decreases when increasing hardness; The peak metatarsophalangeal joint angle wearing hardness shoes was significantly lager than the others.The different hardness of children's shoes midsole will affect the dynamic parameters of the lower limbs of children during running. Children's shoes with appropriate midsole hardness should be selected, which can reduce children's sports injuries and increase running stability, also provides children with certain plantar pressure to promotes development of children's feet.