The greatest distance run on a treadmill in 12 hours (female) is 96.80 km (60.15 miles) and was achieved by Theresa Dugwell (Canada) at the North York YMCA in Toronto, Ontario, Canada on 2 March 2013.

Dugwell ran during the YMCA “Megathon” and broke her previous record of 93.43 km, set the previous year.