Relationships and Significance of Lactate Minimum, Critical Velocity, Heart Rate Deflection and 3 000 M Track-tests for Running

Aim: The running velocities associated to lactate minimum (V(lm)), heart rate deflection (V(HRd)), critical velocity (CV), 3.000 m (V(3000)) and 10 000 m performance (V10km) were compared. Additionally the ability of V(lm) and V(HRd) on identifying sustainable velocities was investigated.

Methods: Twenty runners (28.5+/-5.9 y) performed 1) 3,000 m running test for V3000; 2) an all-out 500 m sprint followed by 6x800 m incremental bouts with blood lactate ([lac]) measurements for V(lm); 3) a continuous velocity-incremented test with heart rate measurements at each 200 m for V(HRd); 4) participants attempted to 30 min of endurance test both at V(lm)(ETV(lm)) and V(HRd)(ETV(HRd)). Additionally, the distance-time and velocity-1/time relationships produced CV by 2 (500 m and 3 000 m) or 3 predictive trials (500 m, 3,000 m and distance reached before exhaustion during ETV(HRd)), and a 10 km race was recorded for V10km.

Results: The CV identified by different methods did not differ to each other. The results (m.min(-1)) revealed that V(lm) (281+/-14.8)<CV (292.1+/-17.5)=V10km (291.7+/-19.3)<V(HRd) (300.8+/-18.7)=V3000 (304+/-17.5) with high correlation among parameters (P<0.001). During ETVlm participants completed 30 min of running while on the ETV(HRd) they lasted only 12.5+/-8.2 min with increasing [lac].

Conclusions: We evidenced that CV and Vlm track-protocols are valid for running evaluation and performance prediction and the parameters studied have different significance. The V(lm) reflects the moderate-high intensity domain (below CV), can be sustained without [lac] accumulation and may be used for long-term exercise while the V(HRd)overestimates a running intensity that can be sustained for long-time. Additionally, V3000 and V(HRd) reflect the severe intensity domain (above CV).