The level of lactic acidosis affects lactate minimum in a heart rate-based lactate minimum test

The aim was to investigate whether the level of lactic acidosis in the first part of a heart rate-based lactate minimum test affects the lactate minimum heart rate and performance. We tested 15 men (age: 31 ± 6 years, height: 179 ± 6 cm, body mass: 75.6 ± 7.6 kg and V˙O(2peak) 50.3 ± 10.0 ml · min (- 1) · kg( - 1)). They all completed 2 lactate minimum tests following 2 different protocols during the first part of the test, i. e., i) a maximal test until exhaustion to provoke extensive lactacidaemia and ii) a submaximal test abandoned 3 stages earlier than the maximal test to provoke significantly lower but still considerable lactacidaemia. The second part of the lactate minimum test was identical for both runs. It consisted of a heart rate-based incremental test to determine the lactate minimum and the corresponding lactate minimum heart rate and performance. Results showed a significantly higher maximal blood lactate concentration at the end of the maximal test compared to the submaximal test (9.7 ± 2.7 vs. 6.0 ± 2.0 mmol · l( - 1), P<0.001). Also mean lactate minimum heart rate (160 ± 12 vs. 144 ± 13 bpm, P<0.001) and performance (200 ± 40 vs. 170 ± 35 W, P<0.001) were significantly higher after the maximal test compared to the submaximal test. We conclude that the first part of the heart rate-based lactate minimum test needs to be performed until exhaustion to receive reliable and meaningful results.