The aim of this study was to observe the behavior of physiological parameters horses undergoing physical exercises and competitions handle the bull correlate with the physical environment using the values of Wet Bulb Globe Temperature (WBGT). 12 crossbred horses race quarter mile have been used aged 5 to 16 years, three with white fur, chestnut coat with four and five dapple coat. The experimental design was completely randomized with two treatments, where a treatment referred to the morning (T1) and other treatment shift to afternoon (T2) shift. Respiratory rate (RR) and heart rate (HR) and WBGT were measured. There was a significant difference (p<0.05) between the two rounds of collections that corresponds to the 1st morning shift (T1) and 2 afternoon shift (T2) for HR, RR and WBGT, with higher rates after the competition in handle the ox. The FC (0.76) positively correlated with the FR and WBGT positively correlated with FR (0.75) and HR (0.86). It can be concluded that horses valued at handle the ox showed physiological changes due to stress associated with exercise.