The Characteristics of Fast Speed Walking in old Men from the Viewpoint of the Ground Reaction Forces

Characteristics of the fast speed walking in old men, primarily from the viewpoint of the ground reaction forces, were investigated in comparison with those during the ordinary speed walking. As a result, the following were recognized as the characteristics of fast speed walking in old men; (1) the walking speed, step length, and brake impulse as well as acceleration impulse began to decrease pronouncedly from the age group in their 60s, (2) the walking of subjects in their 60s and 70s were hastened from the ordinary speed level with almost the same ratios as in the younger subjects, (3) increase of the step length during the fast speed walking, against those during the ordinary speed walking, was smaller in subjects in their 70s than in the younger, (4) increase of the brake impulse during the fast speed walking, against those during the ordinary speed walking, began to decrease from the age-group in their 60s, while (5) that of the acceleration impulse remained unchanged with age. The principal component analysis revealed that (6) the contents of the fast speed walking are almost identical in ages between 20s and 50s, suggesting that they begin to change at one's 60s.