Why Zone 2 Matters for Mitochondria: The training intensity that improves cellular health | Be Well Moments

Why Zone 2 Matters for Mitochondria: The training intensity that improves cellular health | Be Well Moments

Author: Sarah Ann Macklin December 15, 2025 Duration: 6:06

Watch the FULL podcast here: https://youtu.be/7kfykswH6Io


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.

Inigo San Milan in conversation with Sarah Ann


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There's a lot of noise out there about what it means to be healthy, and Live Well Be Well with Sarah Ann Macklin cuts straight through it. Sarah Ann brings a grounded perspective shaped by both personal experience and formal study, moving beyond quick fixes to explore what sustainable wellness actually looks like. Each conversation in this podcast feels like a thoughtful exploration rather than a lecture, tackling the interconnected areas of holistic health, practical nutrition, and realistic lifestyle shifts. You'll hear from a range of insightful guests alongside Sarah Ann's own reflections, all aimed at making sense of the information overload. The tone is refreshingly human-this isn't about perfection, but about finding a smarter, more integrated approach to everyday living. Tuning into this podcast feels like gaining a knowledgeable, empathetic friend who believes that feeling well shouldn't feel like a constant struggle. It’s a space for anyone wanting to move past the confusion and cultivate a genuine sense of vitality that fits into a real, busy life.
Author: Language: English Episodes: 100

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