Here are the “big three” exercises developed by Dr. Stuart McGill, an expert in spine biomechanics at the University of Waterloo in Canada.

These three engage all the important muscles needed to improve spine stability.

Here’s how to perform each of the big three.

You should follow what’s called a pyramid sequence:

  • Start with five repetitions (reps) of each of the three exercises.
  • Then do three reps of each
  • Finish by doing each exercise just once.

As you get more comfortable with the routine, you can increase the number of reps you start with for each exercise, but continue to follow the descending pattern.

Perform these exercises two or three days a week before your regular workout.

Curl-up

1. Lie on your back. Extend one leg straight out on the floor. Bend the knee of your other leg so your foot is flat on the floor.

2. Put your hands under your lower back to maintain the natural arch of your spine.

3. On an exhalation, lift your head, shoulders, and chest off the floor as though they were all connected. (Come off the floor just enough to feel tension in your muscles.) Don’t bend your lower back, tuck your chin, or let your head tilt back.

4. Hold for 10 seconds and then slowly lower yourself down.

5. Complete five reps, then switch leg positions and repeat the sequence to complete the exercise.

Side plank

1. Lie on your side with your upper body propped up on your arm, with your forearm on the floor and your elbow underneath your shoulder. Place your free hand of the top of your hip. Pull your feet back, so your knees are at a 90° angle.

2. Lift your hips off the floor so they are in line with the rest of your body, and hold for up to 10 seconds. Try to maintain a straight line from your head to your knees. Slowly lower your hips back down to the floor.

3. Repeat five times, then flip to your other side and repeat the sequence to complete the exercise.

Variation: For a challenge, straighten your legs instead of bending them.

Bird-dog

1. Get down on the floor on your hands and knees.

2. Raise your left arm and extend it forward as far as possible while simultaneously lifting your right leg and extending it straight behind your body. Keep both the raised arm and leg parallel to the floor. Ensure your hips are aligned with your torso and not tilted to one side.

3. Hold for 10 seconds and then return to the starting position.

4. Repeat five times, then switch to the other arm and leg and repeat the sequence to complete the exercise.