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High-intensity exercise training — too much of a good thing?

Exercise training can induce robust changes in mitochondria that are beneficial for a range of metabolic health outcomes. However, a recent study suggests there might be an upper limit to the amount of high-intensity training that can be tolerated before disruptions to mitochondrial function and whole-body metabolic homeostasis occur.

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Fig. 1: Methodological considerations when interpreting mitochondrial function.


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Work in the authors’ laboratories is, in part, funded by an Australian Research Council grant DP160102176, “Molecular networks underlying exercise-induced mitochondrial biogenesis in humans”.

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Correspondence to John A. Hawley.

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The authors declare no competing interests.

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Hawley, J.A., Bishop, D.J. High-intensity exercise training — too much of a good thing?. Nat Rev Endocrinol 17, 385–386 (2021).

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