To solve problems in physical exercise that exercise is boring, and unsatisfactory, that exercise for developing balance sense, concentration, the legs and the lower back, the trunk, etc., commonly required for various kinds of sports, is not performed sufficiently, that tasks or achievement levels are not clear, and that physical exercise is too simple to provide a sense of energy, resulting in loss of interest.

The exercising tool has elasticity along the whole surface including the inside of the item. Elastic members with different elasticity, or uneven forms, large and small, hard and soft, deformed, or different elasticity, and those with different elasticity, or uneven forms, large and small, hard and soft, and deformed, are differently varied in parts or spots, and properly mixed to compose a solid structure. The exercise tool of the elastic body displacement structure is thus provided with such component elements with resistances to exercising ability that are unfixed, complicated, and unstable to mediums of the exercising tool to show a combined effect. Exercise senses and techniques are spontaneously improved or leaned, thereby exercising environments which are well capable of developing exercising abilities can be established.