A strong core is the foundation of a strong body. Think about it: A tree would fall if its trunk weren't solid and stable. Doing core work isn't just about your middle, either; having a strong core will make you a better runner, surfer, or yogi (or whatever activity you like to do) while improving your posture and balance. Working your core can also protect you from low-back pain — and yes, it’ll tone your abs, too.
One of the best core exercises out there is the plank. “It forces you to stabilize your body, engaging your entire core — not just the exterior abs that you see in the mirror,” says celebrity trainer Anna Kaiser, founder of AKT InMotion studio in New York City. This means that muscles such as your obliques and transversus abdominis will strengthen to give you an even more rock-hard foundation. Plus, you'll work your shoulders and your legs at the same time.
Here, Kaiser has created an easy-to-follow 30-day plank challenge that will get you the benefits of a strong core in no time. You’ll start by planking at an incline (try leaning against a wall, chair, or the back of your couch), which is easier for beginners. Then, as you get stronger, you’ll move to the floor and work your way up to holding a plank or forearm plank (if the high plank, on your hands, is too difficult) for three full minutes.
Your goal will be to maintain proper form the entire time you are holding up your own body weight. This means you will keep your whole body in a straight line, from your heels to your hips to your shoulders.
Aside from sagging hips, Kaiser says the biggest plank mistake she sees is hunched or sliding shoulders. “In order to really engage your abdominals, you want to make sure that your shoulders are directly over your wrists. Normally, when people are doing planks, as the plank continues, shoulders go further back [until] their hands are in front of them,” she says. “That actually puts more of the work in your lower body, so in order to fully distribute the weight and put the majority of the work in your core, you want to make sure to continue moving those shoulders over your wrists.”
“The hardest part about planking is committing — holding still until the end,” Kaiser adds. Her tip for getting through it? A kickass playlist. “If you can distract yourself and listen to a song and say you’re going to get through one more chorus, or you’re going to get through one more song in its entirety, that’s a better way to pace it.”
Want to make sure your plank form is on point? Check out our guide to the fundamentals.