The same old forward motion on the treadmill can get boring. Ramp up your routine by mixing up your treadmill workout. Burn more calories, challenge different muscles and invigorate your enthusiasm for the gym.

Backwards walking: Going backwards pushes your hamstrings and is a good way to stretch out tight hip flexors. Add 5 minutes at the end of a run, or spend a whole 30 minutes going backwards. Set your speed at a slow speed – between 1 and 3.5 mph. Turn around, but hold tight to the handrails to get your bearings. As you feel more stable, begin to let go to train your abdominal and back muscles as well as your legs. You can break into a light jog at higher speeds. Add incline to increase the quadriceps emphasis.

Side shuffles: Adding a side shuffle during your treadmill routine challenges your inner and outer thighs. Begin with a 5-minute warm-up going forward at a comfortable pace. Bring your speed to 2.5 to 3.5 mph and turn sideways, shuffling, for about 1 minute. Return to go forwards for 2 minutes, as fast as you can. Turn the other way and sideways shuffle for another minute. Repeat this workout for 20 to 30 minutes.

Uphill lunges: Set the treadmill incline to 15 percent and your speed to about 1.5 mph. Step forward with your right leg as close to the lip of the treadmill base as is possible and let your left leg drag back into a deep lunge. Repeat with the left leg forward and right leg back. Keep this slow, wide lunge up for a 5- to 10-minute warm-up, as a way to stretch at the end of your workout, or as part of your strength-training routine. These lunges can help on days when your legs feel tight or tired.