Related Experiment Videos
The relationship between lactate and ventilatory thresholds: coincidental or cause and effect?
Summary
Blood lactate (LA) levels were reduced after exercise and diet, suggesting it may not solely drive the
Area of Science:
- Exercise Physiology
- Metabolic Research
- Sports Science
Background:
- The 'breakaway' ventilation (VE) phenomenon is poorly understood.
- Blood lactate (LA) is a potential stimulus for this ventilatory response.
Purpose of the Study:
- To investigate if blood lactate (LA) is the primary stimulus for 'breakaway' ventilation (VE).
- To examine the influence of glycogen depletion on lactate and ventilation thresholds (LT and VT).
Main Methods:
- One-legged cycling exercise with prior exercise and a low-carbohydrate diet to deplete muscle glycogen.
- Monitoring of lactate threshold (LT) and ventilation threshold (VT) using continuous incremental cycling.
- Analysis of blood lactate concentrations and gas exchange during exercise.
- Muscle biopsies to confirm glycogen reduction.
Main Results:
- Glycogen reduction was confirmed via muscle biopsies.
- Blood lactate concentrations at both LT and VT were significantly reduced post-intervention in both exercised and non-exercised legs.
- VO2 and VE remained similar between pre- and post-intervention tests.
Conclusions:
- Reduced blood lactate levels following glycogen depletion suggest LA may not be the sole stimulus for the 'breakaway' ventilation response.
- Further research is needed to identify the specific stimuli triggering the ventilatory threshold.