Active muscle and whole body lactate kinetics after endurance training in men.
Level 3 - non-randomized controlled study
Non-randomized, single-group before-after interventional study
PubMed 10562610 · doi:10.1152/jappl.1999.87.5.1684
What was done
Nine men (mean age 27.4 ± 2.0 years) completed 9 weeks of endurance cycle training (5 days/week at 75% peak oxygen consumption, VO2 peak). Active muscle and whole-body lactate kinetics were measured before training at 45% and 65% VO2 peak, and after training at the same absolute workload as pre-training 65% VO2 peak (ABT) and at the same relative intensity of post-training 65% VO2 peak (RLT).
What was found
Compared with pre-training 65% VO2 peak (4.75 ± 0.4 mM), arterial lactate concentration decreased by 41% at ABT and by 21% at RLT (P < 0.05). Net lactate release decreased at ABT but did not change at RLT. Leg lactate uptake and oxidation were unchanged at ABT but increased at RLT. Metabolic clearance rate was unchanged at ABT but increased at RLT.
Why it matters
The study shows that endurance training decreases exercise blood lactate via distinct mechanisms depending on intensity: reducing production at a given absolute workload and increasing active muscle and systemic clearance at identical relative intensities.
Limits
The sample size is very small (n = 9) and includes only young men, limiting generalizability. There is no non-training control group to control for time or repeated-testing effects.
Cited by
- supports Endurance training leads to lower blood lactate at any given power output because trained individuals have superior lactate clearance and utilization.
- supports Trained athletes produce more lactate than untrained individuals, but clear and remove it more rapidly.