Introduction Biochemical and hemogasometric parameters have been used to evaluate equine performance. This study evaluated blood biochemical and hemogasometry variables of horses during incremental jumping and speed tests. Methods Eighteen horses performed a jumping test with four steps over a vertical obstacle of 1.10 m height (10, 15, 20 and 25 jumps, respectively) totaling 70 jumps, and a speed test with six steps of one minute each with increasing speed from 2 to 8 m/s. Blood samples were collected before and immediately after each test to determine plasma lactate, hematocrit, total plasma protein, glucose, uric acid and hemogasometry variables. Results were analysed by ANOVA and compared by 5% Tukey test. Results Immediately after tests the hematocrit and total plasma protein decreased from 52.4% to 38.9%, and from 7.2 to 6.7 g/dl respectively, and the glucose increased from 98.3 to 109.8 mg/dl (P<0.05). The lactate and uric acid concentrations were higher with speed testing (7.97 ± 4.8 mmol/l and 1.33 ± 0.8 mg/dl respectively) than jumping testing (3.92 ± 3.0 mmol/l and 1.24 ± 0.9 mg/dl respectively). The blood pH was lower after speed testing (7.36 ± 0.1) than the jumping test (7.40 ± 0.04) (P<0.05). Blood pCO 2 , N a and K concentrations increased more after the speed test (53.38 ± 7.3 mmHg/l; 139 ± 3.0 mEq/l; 4.7 ± 0.8 mEq/l respectively) than after the jumping test (49.34 ± 3.2 mmHg/l; 138.3 ± 2.3 mEq/l; 4.51 ± 0.6 mEq/l respectively) (P<0.05). Blood pO 2 was not different among tests (P>0.05). Conclusions Incremental jumping and velocity tests are useful tools for assessing performance of jumping horses. Differences among tests could evidence a smaller anaerobic contribution during jumping test. Ethical Animal Research The study was approved by UFRRJ E thics C ommittee on A nimal R esearch: number 263/2012. Sources of funding: CNPq , CAPES and FAPERJ . Competing interests: none.