how long to break in new shoes before running
Report Abuse. You need to replace shoes every 300 miles, so I would say run at least 30 miles in them before a race, to break them in well. 50 would be optimal, but 30 would be fine. That way you get a week or two to figure out what spots you need to tape or ice pre-race.Good luck in your 5k's!eport Abuse. You need to replace shoes every 300 miles, so I would say run at least 30 miles in them before a race, to break them in well. 50 would be optimal, but 30 would be fine. That way you get a week or two to figure out what spots you need to tape or ice pre-race. Good luck in your 5k's!