ABSTRACT
BACKGROUND:The comfortable shoes can absorb or reduce the impact force from the ground. Is the damped system is absent in shoes to relieve the impulse,the feet will be extremely tired,even damage the human knee joint,waist,back and brain. OBJECTIVE:To measure the changes of human plantar pressure by different sole hardness through the measurement system of plantar pressure. DESIGN,TIME AND SETTING:An observation experiment was performed in the Shanghai University of Sport between December 2008 and February 2009.PARTICIPANTS:Six volunteers wearing the experimental designed shoes were recruited from Nanjing Institute of Physical Education.METHODS:Three pairs of experimental shoes weighing 103 g were measured with shore hardness tester,as 51,62 and 69 hardness values. Accordingly they were named soft shoes,medium hardness shoes and hard shoes. The subjects were asked to do a 60-minute walk test at the speed of 2 m/s on the running platform with the experimental designed shoes,and they were determined using the insole plantar pressure measurement system of German's Novel style series of Emed-pedar.MAIN OUTCOME MEASURE:The pressure,contact area and impulse in the sole of foot.RESULTS:With the increase in hardness soles,the pressure of center plantar was shown to move from the medial first metatarsal outwards by turns. Compared with barefoot walking,the trail length of the center plantar was prolonged in subjects with medium hardness shoes and hard shoes,while shortened in subjects with soft shoes. The total pressure when you walked with soft shoes and medium hardness shoes were reduced than barefoot walking,and the pressure of walking phase wearing these two types of shoes were also reduced,while total pressure and walking phase pressure with hard shoes were both increased compared with barefoot walking. The contact area was similar between soft shoes and medium hardness shoes,but the smallest in the hard shoes. Except the increase in the initial 10 minutes,the soft shoes had no change with the medium hardness shoes. The hard shoes were firstly increased but then declined. The total impulse of medium hardness shoes was the closest to bare feet,while that of soft shoes and hard shoes were increased compared with bare foot.CONCLUSION:The plantar pressure was the greatest in the hard shoes,then medium hardness shoes and last soft shoes;the contact area was the greatest in soft shoes,then medium hardness shoes and last hard shoes;the impulse was the greatest in hard shoes,then soft shoes,and last medium hardness shoes.