The pelvic tilt strengthens the front of your trunk, including your belly muscles.

Here's how to do it.

Start by lying on your back with your knees bent and your feet flat on the floor and your arms at your sides.

Now tighten your belly muscles so that it feels like you're pulling your belly button into your spine.

Your lower back should flatten against the floor while your pelvis tilts up toward your back.

Hold this for 6 seconds, breathing normally, and then release.

Do this 8 to 12 times.

Remember, if an exercise makes you feel worse, stop doing it.