The relationship between the heart rate deflection point test and maximal lactate steady state

BACKGROUND: The aim of this study was to investigate the use of the Heart Rate Deflection Point Test (HRDP) in the determination of the velocity at the Maximal Lactate Steady State (MLSS). METHODS: Fifteen untrained male participants took part in a 3000-m running performance on a 400-m track. The volunteers performed an incremental test for HRDP determination. The third test was constant velocity, which lasted around 30 minutes and was based around HRDP for MLSS determination. RESULTS: Performance velocity at HRDP was strongly correlated with the MLSS running velocity (r=0.84; R-2=0.71; P<0.0001). HRDP running velocity (mean +/- SD 9.0 +/- 1.3-km.h(-l)) was not significantly different (P>0.05) from MLSS velocity (9.3 +/- 1.3km.h(-1)). A high agreement was observed between methods (Bland and Altman analysis) with a mean error of 0.47 km.h(-1). CONCLUSIONS: We can conclude that the HRDP was able to predict MLSS velocity.