This 15-Minute Step Workout Is Easy on the Knees — but Will Seriously Make You Sweat

According to Langhans, this exercise helps strengthen the hamstring and encourages flexion in the knee, as the heel tries to reach for the glute.

• Facing the right diagonal, step onto stepper with the left foot, and drive the right heel towards your glutes into a hamstring curl — foot flexed, arms pulling in as you curl.
• Step off the stepper with the right foot, followed by the left, and repeat facing the opposite diagonal.
• Perform this move for 45 seconds.