Failure to obtain a unique threshold on the blood lactate concentration curve during exercise

Abstract

The purpose of this study was to compare various methods and criteria used to identify the anaerobic threshold (AT), and to correlate the AT obtained with each other and with running performance. Furthermore, a number of additional points throughout the entire range of lactate concentrations [La-] were obtained and correlated with performance. A group of 19 runners [mean age 33.7 (SD 9.6) years, height 173 (SD 6.3) cm, body mass 68.3 (SD 5.4) kg, maximal O2 Uptake (VO2max) 55.2 (SD 5.9) ml x kg(-1) x min(-1)] performed a maximal multistage treadmill test (1 km x h[-1] every 3.5 min) with blood sampling at the end of each stage while running. All AT points selected (visual [La-], 4 mmol x l(-1) [La-], 1 mmol x l(-1) above baseline, log-log breakpoint, and 45 degrees tangent to the exponential regression) were highly correlated one with another and with performance (r > 0.90) even when there were many differences among the AT (P < 0.05). The additional points (ranging from 3 to 8 mmol x l(-1) [La-], 1 to 6 mmol x l(-1) [La-] above the baseline, and 30 to 70 degrees tangent to the exponential curve of [La-]) were also highly correlated with performance (r > 0.90). These results failed to demonstrate a distinct AT because many points of the curve provided similar information. Intercorrelations and correlations between AT and performance were, however, reduced when AT were expressed as the percentage of maximal treadmill speed obtained at AT or percentage of VO2max. This would indicate that different attributes of aerobic performance (i.e. maximal aerobic power, running economy and endurance) are measured when manipulating units. Thus, coaches should be aware of these results when they prescribe an intensity for training and concentrate more on the physiological consequences of a chosen [La-] rather than on a "threshold".

The Role and Development of Sprinting Speed in Soccer

“…Based on these observations, we conclude that the two repeated sprint training sessions were effort matched. However, heart rate values demonstrated a "steady state" condition during repeated 20 m sprints at 90% intensity, and corresponding lactate values were below what has been considered "lactate threshold intensity" (BLa -between 2.5 and 4.0 mmol·L -1 ) in endurance training (Tokmakidis & Pilianidis, 1998). In contrast, repeated sprinting at maximal intensity induced a progressive increase in heart rate, as well as BLa -at or above the typical lactate threshold range described for endurance athletes.…”

Simple Assessment of Lactate Threshold by Means of the Bench Stepping in Older Population

“…Therefore, LA at LT is apparently lower than LA as used to date, and 0.1 mmol/l above resting level would be appropriate. In older individuals, previously described procedures for determining LT that evaluate accelerate increase of LA based on the frequently blood sampling [Beaver et al, (1985) ; Tokmakidis et al, (1998)] was sometime cause the lower accuracy and/or the determination rate, because of the diffi culties in blood sampling above LT [Belman and Gaesser, (1992)]. In this research, similarly, of the 105 subjects who were given the graded exercise test, we were able to obtain suffi cient LA to determine LT in only about half, or 52 subjects.…”

“…B l o o d l a c t a t e c o n c e n t r a t i o n ( L A ) d u r i n g submaximal exercise is closely related to aerobic capacity, especially, lactate threshold (LT) and OBLA (Onset of Blood Lactate Accumulation) are indicators of aerobic capacity better or at least no worse than V ・ of aerobic capacity better or at least no worse than ・ of aerobic capacity better or at least no worse than O 2 max [Yoshida et al, (1987) ; Tokmakidis et al, (1998)]. Because LT in particular can be measured in light to moderate submaximal exercise, it has possibilities for safe and accurate evaluation, in older people.…”

Effect of heavy strength training on thigh muscle cross-sectional area, performance determinants, and performance in well-trained cyclists

“…The critical power has been shown to be a useful fitness measure in trained cyclists (Smith et al 1999) and is related to the maximal lactate steady state (Jones and Carter 2000). Furthermore, it has been shown that any rightward shift of the power output -blood lactate relation reflects improved lactate threshold regardless how the lactate threshold have been determined (Tokmakidis et al 1998). This agrees with the finding that six different methods of determine the lactate threshold all showed significant correlations with 1-h time trial cycling performance (Bishop et al 1998).…”