I think a strong core is just as important as strong legs for running. Your core is like a corset for your body. It keeps you stable when you run, walk, and lift. Pilates is a great way to strengthen your body without putting any stress on it. You will work on aligning your whole body, strengthening your core and fixing any muscle imbalances, all with small controlled movements.

I’ve been doing Pilates for ten years, and it’s helped me finish five marathons and rebuild my core after having my baby two years ago. The side-lying double leg lift is one of my favorite ways to work my obliques and the muscles in my inner and outer thighs. Keep reading to learn more.

If you’re getting back into exercise after a long break, you’re a total beginner you’re recovering from an injury, or you’re pregnant or just had a baby, it’s always best to talk to a qualified professional for personalized advice first.

What is the exercise, and how do you do it?

The Pilates side-lying double leg lift looks a lot easier than it is, but it’s a great way to work your deep core, internal and external obliques, and thighs. You only need your body weight for this exercise, but it might be more comfortable to lie on one of the best yoga mats.

Here’s how to do it:

Put your head on your lower arm or extend your arm out in line with your body and rest your head on it. Put your other arm in front of you.
Stack your hips and shoulders, and then move your legs a little bit in front of your hips to keep your balance.
Think about bracing your core as if you were about to be punched, and zip up and in your deep core and pelvic floor muscles.
Squeeze your inner thighs together and lift both legs up toward the ceiling. Use your obliques which are the muscles that run along the sides of your abs, to control the movement.
Stop at the top, then carefully lower both legs back to the mat.

Your hips should stay in line with each other during the whole exercise movement. Don’t rock back or arch your back. Try to do 6 to 10 reps on each side, and don’t switch sides until you’ve finished all of your reps.

What are the good things?

Strong obliques

The leg lift here must come from your obliques, not your hips even if you only manage to lift your legs a few inches off the ground, really focus on moving from your core. As both legs lift, you’ll be firing into the inner and outer obliques, but your deep core muscles, the transverse abdominis, will be working hard to keep your body stable as you move.

Targeting the deep lower back muscles

This exercise also works the quadratus lumborum — a deep muscle in the lower back that stabilizes your spine and pelvis. A weak QL muscle is the primary source of deep lower back and lateral hip pain, so this is a good one to target, especially if you spend a lot of time sitting behind a desk.

Working into the thighs

Those little leg lifts they’re working the inner and outer thighs or the adductors and abductors if you will. As you lift the top leg will work the glute medius and TFL muscle to lift against gravity while at the same time, the bottom leg will be working the adductors to stay lifted from the ground. This, in turn, can help improve your hip stability, reducing your risk of knee strain during exercise and helping you move with better balance.

Targeting lateral stability

If, like me, you’re a runner, you’ll spend a lot of time moving in a traditional forward and back plane of motion. This exercise works in a frontal plane, helping you master lateral stability, which is essential for improving balance and reducing injury risk.

What are the progressions?

Once you’ve mastered this exercise, you can increase the intensity by adding additional equipment, or instability:

Add weights a resistance band, or a Pilates ball you can easily add additional load to the exercise by adding equipment like ankle weights around your ankles to make your legs work harder. You can also place a mini-band around your ankles or thighs and push against the band as you lift. This will force the glute medius to work harder as you lift. You could also put a Pilates ball between your ankles and squeeze it as you lift. This can help get the pelvic floor and inner thigh muscles moving.
Raise your arm to the ceiling. The less support you get from the floor, the harder your core has to work to keep your body stable. Instead of putting your top hand on the floor in front of you, stretch it out to the ceiling or rest it on your top hip instead.