1 Investigation of the Dynamic Characteristics of Cardio-Respiratory Response OT Treadmill Running Exercise for Interval Training

Interval training is an effective method of improving aerobic function and cardiovascular fitness. Heart rate (HR) and oxygen uptake (VO2) are major indications of human cardiovascular response to exercises. This study investigated human heart rate as well as oxygen uptake response dynamics to running exercise. Three healthy male subjects were asked to run on a motor-controlled treadmill under a predefined running protocol. Heart rate and oxygen consumption were monitored and recorded by using a COSMED portable gas analyzer (K4b2, Cosmed). The running protocol was repeated twice by each subject to reduce the influence of various internal and environmental factors on the heart rate and oxygen uptake measurements. Experimental results showed that the time constant of offset exercise for both heart rate and oxygen uptake is longer than that of onset exercise; they also showed that VO2 reached the steady state faster than heart rate for both onset and offset cases. This study also showed how onset and offset time constants as well as onset and offset steady state gains of VO2 profile can be used to set up an appropriate interval training protocol to improve human fitness.