Exercise ball on the wall calf raise (tennis ball between ankles)

Stand facing a wall with your feet shoulder-width apart. Place an exercise ball between the wall and your lower back. Hold a dumbbell in each hand, with your arms extended by your sides. Place a tennis ball between your ankles. Raise your heels off the ground, lifting your body up onto your toes. Pause for a moment at the top, then slowly lower your heels back down to the starting position. Repeat for the desired number of repetitions.