The wall sit exercise strengthens your back, trunk, and thigh muscles, helping you maintain a healthy lower back.

1. Stand with your back 10 in. (25 cm) to 12 in. (32 cm) away from a wall.
2. Lean into the wall until your back is flat against it.
3. Slowly slide down until your knees are slightly bent, pressing your lower back into the wall.
4. Hold for a count of 10, then slide back up the wall.
5. Repeat 8 to 12 times.