Excessive walking and running can cause foot injuries due to continuous high impact force and pressure on the foot sole, especially in the heel and the forefoot regions. This problem can be relieved with insoles made of various cushioning materials. The cushioning pads of insoles at forefoot and heel regions significantly influence plantar pressure and reduce the forces during walking and running. However, no studies have compared the mechanical properties of different cushioning materials as regards decreasing the plantar pressure and forces during these activities. The effects of different cushioning materials on the reduction of force and pressure at forefoot and heel regions, especially during running, were compared in this study. Mechanical properties of insoles for compression, hardness and cushioning were evaluated and analyzed. Moreover, the plantar pressures measured by the Pedar X system were collected and compared among volunteers. It was found that the EVA additional pad improves the cushioning by the insole. However, an insole made of PE was the best pad for reducing plantar pressure during both walking and running activities. In addition, the relationship between plantar pressure reduction and compressive property of insoles was found.