"This is one of the most underrated Pilates exercises"—an expert instructor on the core move everyone should add to their workouts

Building a strong core is one of the best fitness goals you can have. In fact, it can transform the way your body feels and moves in everyday life, as well as during exercise. The core is often referred to as the powerhouse in Pilates, and a strong core provides a stable foundation for all movement.

Because of its role in all movement, just strengthening your core with crunches or planks is too limited, and it's best to add variety to your core workouts.

Pilates instructor Catherine Manna, founder of CLM Pilates, told me there's one core exercise that lots of people don't know about, but could benefit from. "This exercise is called swimming, which is one of the most underrated Pilates exercises in my opinion," says Manna. "Instead of being on your back or sitting up, which a lot of core stuff is, you're on your front, laying down in a prone position," Manna explains.

If you've never done Pilates before, it's a style of exercise that incorporates slow and controlled movements that increase the time your muscles are under tension to help you build strength, so it's worth keeping this in mind when trying this exercise.

"It's a controlled movement so you're not flapping your arms and legs everywhere—you're keeping your core really engaged," says Manna.

As well as targeting your core, this exercise will also strengthen your back. "We spend our whole lives looking at phones, so it's nice to incorporate the back which supports our core too," says Manna.

You don't need any equipment, although a mat will make the experience more comfortable.

How to do Pilates swimming

(Video credit: selected-takes / Getty Images)

• Lie face down on a mat with your arms extended forward and your legs extended. Engage your core and lift your head off the mat, keeping your neck long and aligned with your spine.
• Inhale as you lift your arms, chest and legs off the mat. Keep your core engaged and your gaze downward to avoid straining your neck.
• Exhale as you alternate lifting your right arm and left leg slightly higher, then switch to your left arm and right leg, creating a fluttering motion. Move quickly but with control.
• Continue the alternating motion for 5–10 breaths, keeping your core engaged and your movements slow and controlled.