Commonly used metabolic thresholds: agreement and occurrences among runners

Denis R, Bottoms L, Holland C. Commonly Used Metabolic Thresholds: Agreement and Occurrences Among Runners. JEPonline 2021;24(3):97-109. The purpose of this study was to investigate lactate (LAth), ventilatory (VEth) and gas exchange (GEth) thresholds agreement and occurrences among recreational runners. Nineteen runners (mean ± SD maximal oxygen uptake [V̇O2 max] 50.7 ± 5.1 mL·kg–1·min–1) completed two incremental treadmill tests to determine their thresholds and V̇O2 max. A repeated measures ANOVA was performed to compare the differences in V̇O2 and HR values between each threshold. Bland-Altman plots were used to compare agreement between the thresholds. No significant differences were found between the V̇O2 and HR values associated to the thresholds. For all comparisons made, the correlations were medium to large. Bland-Altman plots showed agreement between V̇O2 at LAth and GEth ( bias = − 0.25, LOA = – 7.24–6.74), at GEth and VEth (bias = −0.77, LOA = −4.55–3.00), as well as at VEth and LAth (bias = −1.02, LOA = –9.08–7.03). HR at LAth and GEth had larger LOA (bias = –2.31, LOA = –20.80–16.17). This was also true for the agreement between HR at GEth and VEth (bias = –1.79, LOA = –10.71–7.13) and HR at VEth and LAth (bias = –4.10, LOA = –25.17–16.96). There was a better agreement between GEth and VEth than LAth and VEth or LAth and GEth. Therefore, the extent of disagreement between lactate and ventilatory derived thresholds suggests that they should not be used interchangeably in the context of a training prescription for recreational runners.