Rear lunges work to tone your legs, thighs and lower back muscles. To save your time it is a good technique to combine different exercises to get the maximum benefits of workouts. A combination of lunge exercise with single arm raise works on different muscles at the same time. Holding dumbbells enhances the intensity of the exercise. You should use weights to perform this combination exercise as per your fitness level. It is one of the best workouts you can do to tone your upper and lower body together. These kinds of exercises are easy to perform and can be done by anyone at any fitness level.