VALIDITY AND ACCURACY OF BLOOD LACTATE MEASUREMENTS FOR PREDICTION OFMAXIMAL ENDURANCE RUNNING CAPACITY - DEPENDENCY OF ANALYZED BLOOD MEDIA IN COMBINATION WITH DIFFERENT DESIGNS OF THE EXERCISE TEST

The effect of using different blood lactate sampling sites in combinat ion with different exercise test designs on the validity and accuracy for prediction of maximal endurance running velocity was investigated. Ten aerobically all-round trained firemen and nine aerobically endura nce trained long-distance runners performed six differently designed t readmill running blood lactate accumulation tests. Each test consisted of five consecutive running periods on a treadmill of either 4, 6 or 8 min duration, with a mean increase in running velocity between each period of either 0.25 or 0.5 m s(-1). The corresponding treadmill runn ing velocity to a lactate concentration of 4.0 mmol l(-1) in capillary and venous hemolysed blood and plasma for each running velocity. The mean running velocity from a maximal 12 km run for the firemen and a m aximal 21 km run for the runners served as the reference of maximal en durance running velocity. There were both significant (p < 0.001) and similar relationships (r = 0.86-0.94) and no difference in mean predic tion error between the predicted and measured maximal endurance runnin g velocities with all tested protocols. However, there was a high risk of making both over- and underestimations (5% to -4%). The lowest ris k of making an inaccurate prediction was found when a running duration of 8 min for each running period was used in combination with an incr ease in running velocity of 0.25 m s(-1), and the lactate measurements were performed in hemolysed capillary blood.