You have your routine. You hop on your favourite treadmill by the window, cue your favourite playlist, podcast, or show, and do your same basic run. If it is familiar to your, it's familiar to your muscles, so you'll likely hit a plateau. The remedy? Mix things up! Aim to do a different treadmill workout every time you hop on the machine by mixing up the speed, adjusting the incline, and changing the duration of your runs. And every once in a while, use the elliptical or run outside! And if you run outside, change your route up.