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Why is zone two training so important for mitochondrial health? It’s linked with improvements in fat oxidation and lactate clearance, which are used as surrogates of mitochondrial function in sports science.

This clip explores how different exercise intensities drive distinct metabolic responses, why athletes are useful models for understanding cellular energy, and how laboratory testing with metabolic carts and lactate measurements led to practical training zones from easy efforts to sprints.

I’m exploring with my guest how zone two work consistently improved fat oxidation and lactate clearance in testing, while higher intensities remain essential for performance and VO2, since competitions are decided at the top end.

Here, I’m discussing the balance between building a metabolically efficient engine at the mitochondrial level with zone two, and training the “turbo” at zones four and five plus sprint work for race demands, all in clear, everyday language you can apply.

As a nutritionist and health communicator, my aim is to translate these lab insights into practical training decisions that respect both mitochondrial function and cardiorespiratory adaptations.

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