1. 1) Paffenbarger, R. S.: All-cause mortality, and longevity of college alumni. N. Engl. J. Med. 314, 605-613, (1986).
2. 2) Kraus, H.: Hypokinetic Disease, C. C. Thomas pub, (1960).
3. 3) Himann, J. E., Cunningham, D. C., Rechnitzer. P. A. et al.: Age-related changes in speed of walking, Med. Sci. Sports Exec., 20, 161-166, (1988).
4. 4) Kaneko, M., Morimoto, Y., Kimura, M. et al.: A kinematic analysis of walking and physical fitness testing in elderly women, Canad. J. Sports Sci., 16, 223-228, (1991).
5. Relation between muscular function of the quadriceps femoris and walking capacity.