The degree of fitness as ascertained by performance of a modified Harvard Step Test did not increase over controls for isometrically trained individuals. However, improvement over a prior training period was apparent. The breathing rate is probably a satisfactory index of measurement for the Harvard Step Test but needs further elucidation.
Proceedings of the Iowa Academy of Science
©1965 Iowa Academy of Science, Inc.
Swan, Wallace A. and Cook, Kenneth M.
"The Effects of Isometric Contractions on Breathing and Pulse Rates in the Performance of a Modified Harvard Step Test,"
Proceedings of the Iowa Academy of Science, 72(1), 518-523.
Available at: https://scholarworks.uni.edu/pias/vol72/iss1/73