Etological and physiological tests were realized on 48 horses. There were observed following activities: spontaneous kinetic activity, voice display; the elimination behavior (excretion and urination) and motionless standing. The horses were observed in 40 minute periods during the morning hours. The horses were classed into the following groups: EHB+ - crossing more than 220 sq. per 40 min. (high sensitiveness to stress), EHB+/- - crossing 131 - 220 sq. per 40
min. (mean sensitiveness to stress), EHB- - crossing 130 and less sq. per 40 min. (low sensitiveness to stress). After the evaluating of mineral, energetic, lipid, nitrogen, and enzymatic profile of sport horses there were not observed significant differences from the reference values.