Length: 8 minutes Equipment: Stability ball Type of Workout: Strength training (toning) & flexibility Muscles Worked: Lower body (quads, glutes, hamstrings, calves) Fitness Level: Beginner to intermediate Impact: Low-impact Safety Precautions: Warm up before starting this workout and wear athletic shoes. Make sure your ball is well-inflated. Extra Tip: To make this workout harder, you can hold dumbbells at your sides during each exercise.