HOW: Set up a small step on the ground. Step up onto the step with one leg as you bring the other leg up bending the knee and your hip into a 90 degrees angle each. As you drive your knee up, raise your opposite arm straight up overhead into a reach. Return that leg to the ground and place your full weight onto it. Continuously perform this motion for the prescribed amount of reps.
FEEL: You should feel your leg and hip muscles working.
COMPENSATION: Keep your upper half upright, don’t slouch forwards as you step up and back. Don’t rush, pause at each step in the exercise.