Monitoring training success using a lactate-speed relationship

Monitoring training by measuring blood lactate content is a well-known procedure in sports physiology. Because of the difficulties in standardizing a test procedure in field studies, this method is fraught with considerable problems when applying it to race horses. The aim of the present study was to develop a test procedure which is able to give evidence about the training state of different race horses after nonidentical test-loads. Under almost identical environmental conditions, the level of blood lactate was determined in five trotters which were kept in training. Immediately after the single phases of a three-stage test procedure (handicap: 'small', 'medium' and 'high' load for the animals chosen at the discretion of the coach) blood samples were drawn. The lactate value was set in relation to the speed of each animal. A curve of the equation y = y0 + e(k + b*x) was fitted with r2 > 0.93 to these data. With the aid of this equation, the 'comparative speed', V, was calculated; this is the arithmetic mean of the velocities V4, V8 and V20, obtained by inserting the appropriate values for (imaginary) lactic acid concentrations in the formula. With the aid of V it was possible to detect both an increase and a decrease in physical fitness. In this way, animals tested together on one date, as well as the development of one animal tested on several dates, can be scored. Advantages and limitations of the method are discussed in detail.