A Ballerina’s Blistering, Not-for-Beginners Routine

Kathryn Boren of American Ballet Theatre needed to get stronger, so she built a demanding fitness regimen around extreme balance exercises

Ballet dancer Kathryn Boren has long, thin legs that seem well-suited to ballet. But to rise to the top of American Ballet Theatre, she needs muscle. Lots of it.

Ms. Boren, 25, has been dancing professionally since 2009, first with ABT’s junior company, then in Berlin and Boston. She returned to New York in 2015 for a coveted spot in ABT’s corps de ballet, or ensemble. After her first season with the company, she decided to work on her strength and stamina like a pro athlete.

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