Some people like to base it off a half-marathon PR, multiplying it by two and adding somewhere between 10 and 15 minutes. But there’s another method, favored by some coaches, based on your 10K time.

Some 14,000 participants took part in the Transamerica Rock ‘n’ Roll Denver Half marathon and 10K run in Civic Center park on October 16, 2016 in Denver, Colorado. The weekend race incl… ...