A Brief History of Interval Training: The 1800's to Now

⏱️ Entertaining and informative article on the history of intervals. ****

https://www.scienceofrunning.com/2016/08/a-brief-history-of-interval-training-the-1800s-to-now.html?utm_campaign=shareaholic&utm_medium=email_this&utm_source=email

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