A protocol for the determination of the maximal lactate steady state in working dogs

Abstract

This study aimed to describe a test protocol for the determination of the maximal lactate steady state (MLSS) in dogs. Ten animals were submitted to a variable number of sessions (3 to 5), with a duration of 30 minutes each. Every session started with a warm-up period of 10 minutes at 7 km/h, at a 0% inclination. The treadmill was then set at a 5% inclination and at a constant speed, maintained for 20 m. In subsequent sessions, speed was increased or decreased 0.5 km/h. Blood samples were collected, and blood lactate (BL), heart rate (HR), rectal temperature (RT) and glycaemia were determined at rest (T0), after the warm-up (T1) and every 5 minutes until the end of the test (T2-T5). Significant variations were observed in BL, HR and RT, when comparing values at rest and T1 with those at the MLSS level (P<0.01). Mean speed at MLSS was 14.6±1.47 km/h and BL was 2.7±0.45 mmol/L, a value below 4 mmol/L. A correlation between BL at MLSS and the visual lactate threshold was observed (0.87). A strong agreement between blood lactate levels at the MLSS level and LTv was also observed. The present results consist, to the authors' knowledge, in the first description of a protocol to determine the MLSS in dogs. It provides information for exercise monitoring and training planning.