Effect of ramp slope on different methods to determine lactate threshold in semi-professional soccer players

摘要

The present study aimed to investigate the effect of stage duration in incremental protocols on lactate threshold (LT), determined by different methods. Sixteen semi-professional soccer-players performed a 4-min stage incremental discontinuous (DP) and two maximal incremental running continuous (1 km h(-1). min(-1), CP1; and 1 km h(-1).2 min(-1) CP2) protocols. Blood-lactate concentration [La-] was measured at baseline and during the protocols. LT was determined using D-MAX, DMAX-MOD, 4-mM.L-1, Delta 1-mM.L-1 and Log-Log methods. Log-Log showed no difference in LT between CP1, CP2 and DP. Conversely, LT was determined at higher velocity in CP1 than CP2 for D-MAX (15.2 +/- 0.5 vs 14.4 +/- 1.2 km.h(-1), P = 0.002), DMAX-MOD (16.0 +/- 0.5 vs 14.7 +/- 1.3 km.h(-1), P < 0.001), 4-mM.L-1 (15.5 +/- 1.4 vs 14.4 +/- 1.2 km.h(-1), P < 0.001), Delta 1-mM.L-1 (15.5 +/- 1.3 vs 14.4 +/- 1.2 km.h(-1), P < 0.001). Higher LT in CP1 than DP for D-MAX (15.2 +/- 0.5 vs 13.0 +/- 1.0 km.h(-1), P < 0.001) and DMAX-MOD (16.0 +/- 0.5 vs 13.6 +/- 1.6 km.h(-1), P < 0.001) was found (P < 0.001). Log-Log resulted in shorter but accurate protocols to determine LT.