Effect of show jumping on heart rate, blood lactate and other plasma biochemical values

This study investigated some physiological responses to exercise performed by a horse during show jumping. The effects of jumping on heart rate (HR), blood lactate (LA) and some other blood values were studied in nine normal horses participating at the Belgian Junior Championship. Venous blood was sampled before and immediately after the show jumping and was analysed for packed cell volume, LA, blood glucose (GLU), total plasma protein, bicarbonate, sodium, potassium (K+), chloride, calcium and activities of plasma lactate dehydrogenase, creatine phosphokinase (CK) aspartate amino transferase and gamma glutamyl transferase (GGT). A heart rate recorder placed under the saddle allowed the continuous recording of HR from the warm-up until 2 mins after the event. The completion of the jumping induced significant changes in all values, except in K, GLU and GGT. Resting values of LA and HR were 0.53 +/- 0.05 mmol/litre and 43.9 +/- 1.9 beats/min respectively. Post exercise LA reached a mean value of 9.04 +/- 0.9 mmol/litre, and, during the jumping, HR rose to a peak of 191.4 +/- 3.8 beats/min. The results of this study demonstrate that, although the speed and duration of such an exercise are low, show jumping represents a severe exertion which requires the use of anaerobic metabolism. This implies that the training schedule of jumpers must include power training in order to improve their anaerobic capacity.