The purpose of this study was to compare the effects of step frequency (SF) variations on cardiorespiratory responses in women. Six healthy university students participated as subjects. The subjects performed five 10 min altered SF treadmill walkings at the three fixed speeds, i. e., 60, 80 and 100 m・min⁻¹ respectively. The five trials involved walking with a freely chosen SF (FCSF) and a FCSF altered by +10%, +20%. -10% and -20%. Following determination of the FCSF at fixed speed, each subject performed walking at the same speed with four randomly ordered SF, ± 10% and ± 20% from the FCSF, conditions.
　Determinations of oxygen uptake, heart rate, blood pressure (SBP/DBP), PRP and RPE were made during 4~6 and 8~10 min. All subjects showed a significant increase (P< 0.05) in oxygen uptake and RPE when walking at either the low or the high frequency of SF when compared to the FCSF at the all speeds. There were no significant differences in heart rate, blood pressure (SBP/DBP) and PRP in the five trials at all the speeds. The results of this study suggest that walking with a decreased SF from the FCSF, long step length, may be one of the advantageous aerobic exercises for the improvement of aerobic work capacity.

DESCENTE SPORTS SCIENCE Vol.12/THE DESCENTE AND ISHIMOTO MEMORIAL FOUNDATION FOR THE PROMOTION SPORTS SCIENCE