A housing 1 is provided with a left foot support 2a and the right foot support 2b each of which is provided for bearing the user's foot thereon. A drive unit 3 is configured to vary an upper surface angle of each of the left foot support, 2a and the right foot support relative to horizontal plane. Each of the left foot support 2a and the right foot support 2b is driven to move within a swing range. When one of the left foot support 2a and the right foot support 2b has its front end being located at an upper end of the swing range, the other of the left foot support 2a and the right foot support 2b has its front end being located at a lower end of the swing range. Both of a left ankle joint and a right ankle joint are alternately dorsiflexed and plantarflexed. Consequently, it is possible to obtain an exercise assisting device being configured to bend and stretch lower legs to stimulate lower leg muscles.
