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Influence of different RAMP test protocols on peak blood lactate parameters in runners

Peak blood lactate concentration (Lpeak) after exhausting exercise is often considered as a measure of the anaerobic glycolitic capacity. The aim of this study was to compare peak and recovery blood lactate parameters, measured in runners of diverse running disciplines, after performing two all-out treadmill ramp tests of different duration. The sample consisted of 48 male runners: 10 sprinters (S, 20.5± ; 3.0 yrs, 184.9± ; 4.8 cm, 76.6± ; 4.4 kg), 15 400m runners (400R, 20.0± ; 3.5 yrs, 180.9± ; 4.2 cm, 73.0± ; 6.3 kg), 10 middle distance runners (MD, 18.7± ; 2.3 yrs, 180.4± ; 5.7 cm, 68.6± ; 6.2 kg), and 13 long distance runners (LD, 27.0± ; 5.8 yrs, 179.1± ; 6.7 cm, 69.5± ; 7.0 kg). All subjects performed two incremental treadmill tests to exhaustion, with the starting running speed of 7 km/h, at a constant inclination of 1.5%.The increase in speed of locomotion was: a) 1 km/h each ½ ; minute (F05-test), b) 1 km/h each minute (F1-test). Finger-tip capillary blood lactate concentration was measured at the end of the 1st, 3rd, and 5th minute of recovery (L1, L3, L5). The highest of the three readings was considered as Lpeak. Two-way ANOVA was used to determine differences in the measured variables between the two tests in each subject group. The average test duration was 7.6± ; 1.0 min (F05) and 13.0± ; 2.1 min (F1). The following peak blood lactate concentrations (mmol/L) were measured after the F05-test: 15.1± ; 1.4 (S) ; 14.3+/-1.4 (400R) ; 13.5± ; 3.3 (MD) ; and 10.4± ; 2.0 (LD). After the F1-test Lpeak values were: 15.1± ; 2.7 (S) ; 14.0± ; 1.4 (400R) ; 13.7± ; 2.9 (MD) ; and 10.9± ; 2.4 (LD). No significant differences between the Lpeak measured after the two tests within each subject group were found. The measured time to reach peak lactate concentration (tLpeak(min)) was as follows: F05-test (2.4± ; 1.4 (S) 3.1± ; 1.4 (400R) ; 2.0± ; 1.1 (MD) ; and 2.4± ; 1.3 (LD)) ; F1-test (1.2± ; 0.6 (S) ; 1.9± ; 1.5 (400R) ; 1.8± ; 1.4 (MD) ; and 1.5± ; 0.9 (LD)). A significant difference in tLpeak measured after the two tests was found only in the 400R group. The tLpeak was significantly longer after the F05 test (p=0.039). Similar peak blood lactate values were achieved in the recovery period of both test protocols used in this study, regardless of the running discipline. On the other hand, the time to reach peak blood lactate concentration was longer after the short (F05) test in all the subject groups, reaching the statistically significant level only in 400R runners. For practical implications, the duration of an all-out incremental treadmill test does not significantly influence the Lpeak value, if volitional exhaustion is reached within 5 to 15 minutes, approximately. Nonetheless, the timing of recovery blood sampling should be chosen with caution, and taking two or more samples may assure the acquirement of true peak lactate values. References. Bentley D.J. et al (2007). Sports Med, 37(7):575-86. Vucetic V. (2007). Unpublished doctoral thesis.University of Zagreb. Smith P.M. et al (2006).

ramp test protocols; blood lactate; runners

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