The One Move That'll Help You Get Strong, Toned Abs FAST

It's time to stop cranking out endless crunches if you want to achieve killer abs. Holly Perkins, C.S.C.S., recommends one basic move that you can do in your living room: the single-leg holding plank. "It's a bit challenging, but it's super effective," she says. "It hits your whole core from a functional and aesthetic perspective." In other words, this exercise will shore up your core—which makes daily movements easier—and give your tummy a toned appearance.

Here's how to do it: Start in pushup position, then drop down so your elbows are supporting your upper body (standard plank position). Make sure your body forms a straight line from head to heels. Tighten your abs, then lift your left foot about two inches off the ground. Hold for five seconds, then return to the starting position. Repeat on your right side. Continue alternating legs until you've completed 10 repetitions per side. Do three sets total.
Maintaining good form is essential to making this move effective. Perhaps the most critical component is contracting your abdominal muscles before lifting your leg—otherwise, you might push out your abs during the exercise. "Over time, that could put strain on the muscles of your lower back," warns Perkins. And when you lift your foot off the ground, don't allow your hips to rotate to either side. "Nothing in your body should move except the one leg," says Perkins.

Want to challenge yourself even more? Double the amount of time you hold up each leg, and complete 15 repetitions per side instead of just 10.