Lactate

A byproduct of glucose metabolism produced during intense exercise. It is not waste, but fuel. Its concentration in the blood (lactate threshold) marks the boundary between Zone 2 and higher intensities.

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Zone 2 Training: The Foundation of Metabolic Longevity

You don't have to run until you pass out. Discover why low-intensity training is the secret to healthy mitochondria and metabolic flexibility.

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