A manual treadmill can seem intimidating. Maybe you’ve only ever seen them in garage gyms or in CrossFit. We test all kinds of treadmills, and manual treadmills are some of our favorites. No max speed, low maintenance, built to last, and improved running form; yeah, curved, non-motorized treadmills do all of this and more. Find out why you need one and which of these best manual treadmills is for you here.