Reproducibility of the blood lactate-running speed curve in horses under field conditions.

The research explores the consistency of parameters obtained from the blood lactate-running speed curve of sport horses, utilizing two methods of calculation: a curve-fit equation and linear interpolation. Findings showed the highest reproducibility at velocity inducing 3.5 and 4 mM blood lactate concentration, establishing its appropriateness in comparing horses and evaluating conditioning effects.

Goal of the Study

• The aim of this research was to study the reproducibility of blood lactate-running speed curve parameters in sport horses. The curve parameters were obtained using two methods: a curve-fit equation and linear interpolation.

Methodology

• Thoroughbreds were subject to a 4-speed test, consisting of four runs over 2,110 meters. The intensity of the exercise increased by 1 meter/second for each run.
• After each run, blood lactate concentration was measured and plotted against the running speed, establishing the blood lactate-running speed relation.
• This relation was used to calculate the velocity inducing 2, 2.5, 3, 3.5, or 4 mM blood lactate concentration by a curve-fit equation and by linear interpolation.

Results

• The analysis revealed that the correlation between the test-retest of velocity at varying levels of blood lactate concentrations was significant. The correlation was most reliable at the highest blood lactate concentrations using both calculation methods.
• The reproducibility was best for velocity inducing 3.5 and 4 mM blood lactate concentration, as the test-retest regression matched the identity line in these cases.

Conclusions

• This research concluded that the reproducibility of velocity inducing 3.5 and 4 mM blood lactate concentration is strong enough to be used for comparing horses and assessing conditioning effects. This conclusion applies to both methods used to calculate parameters from the blood lactate-running speed relation.