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What is the difference between a treadmill and a stair climber?
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A treadmill is a machine that simulates walking or running on a flat surface, while a stair climber is an exercise machine that allows you to simulate climbing stairs. Both machines can be used to exercise your legs and build strength, but they do so in different ways. A treadmill typically has a belt that moves back and forth under your feet as you walk or run, while a stair climber usually consists of steps that you climb up and down.