An integral part of yoga and Pilates, planking is a popular core-strengthening exercise. But over the past few years, it’s gotten some negative press, with claims that the ab-busting move contributes to serious back problems. LivingHealthy expert and Beyoncé’s trainer Marco Borges, founder of 22 Days Nutrition, sets the record straight on who should and shouldn’t be planking and gives us a lesson on how to master the move without getting hurt.

“Planks, like many other exercises, can be very effective if done properly, but can also cause trouble if done incorrectly,” Borges states. “I think the biggest problem comes from beginners jumping right into planks without proper technique, which can cause strain in the lower back.”

A proper plank is done lying facedown (like you’re about to do a push-up) with the palms—or forearms for beginners—planted on the floor, slightly wider than shoulder-width apart. Digging your toes into the ground and squeezing your glutes for stabilization, press your entire body up until your arms are straight. If you’re a beginner, keep your elbows bent at a right angle with your forearms on the ground for support.

“Make sure you are looking slightly forward and not down. Draw in your belly button and hold the position,” Borges adds. During your plank, be sure to keep your core tight and back straight (with a neutral spine). “There should be a straight line down your body from your shoulders to your heels,” Borges explains. “Your hips should not drop or sag. Dropping your hips might make it feel easier, but what it actually does is place all of the pressure on your lower back, making the move much less effective—and may even compromise the health of your back.”

If you have a pre-existing back health problem, Borges advises checking with your doctor or a specialist before trying planks. But if you have occasional back pain (possibly due to sitting at a desk for too many hours a day), planks can contribute to strengthening the core muscles, which will help to support proper posture and alleviate undue stress on the back.

So unless you have a doctor’s note or can’t figure out how to do a plank properly, you have no more excuses not to firm up those abs this summer!