Aerobic decoupling, or cardiac drift, are the terms commonly used to describe the progressive increase in heart rate over a prolonged period of endurance exercise, when the work rate (for example cycling power output or running pace) does not increase. The ability to produce high power outputs at the end of a long day in the saddle, or after mulitple days riding in multi stage events is what separates the very best cyclists from those they leave behind. In this presentation Dr Helen Carter discusses the concepts of aerobic decoupling or cardiac drift, how we can quantify decoupling in our training data and strategies to use these concepts to improve our cycling performance.

You may also be interested in reading more about the concept in the PBscience fact sheet on aerobic decoupling:

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