Dr. Andrew Best is a professor at the Massachusetts College of Liberal Arts where he focuses on evolutionary questions about human physiology. You can email him at andrew.best@mcla.edu.

His latest study was titled "Ultra Endurance Athletes and the Metabolic Ceiling." They looked at the maximum, sustainable amount of energy expenditure that can be done over a long time period. It answers the question, "what is the limit of human energy expenditure?"

It's a metric that literally dictates how hard you can train. If you want sustainable performance, you'll love this episode.

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I was recently at a weekend physical therapy workshop (lol I was the only running coach) and learned how important (and rare) this simple movement is. Save 10% with code STRENGTHRUN10 at checkout at moboboard.com.

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