I have had my treadmill for almost a year and I use it daily. I do not consider myself a serious runner, but I do run on it and also use it for sprints...both with no problems at all. I am about 140 lbs and the motor handles my weight and speed with ease. My husband occassionally uses it as well and he is pushing 275 lbs. I have not been disappointed with this purchase and would recommend it to anyone wanting a moderate workout.