To take yourself from 20 or 30 minutes on the treadmill to the finish line of a charity 5K (3.1 miles), follow this plan from running coach Jason Karp: Instead of running two miles three times a week, run different distances each day. Go two miles on Monday, one on Wednesday, and three on Friday. Each week, increase each run by five to 10 minutes (so a 2/1/3 pattern becomes 2.5/1.5/3.5 the next week, 3/2/4 the following week, etc.). Try to get your longer run up to at least five miles.
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