The key is knowing how to do a plank, however. As good as the exercise is, you have to do it exactly right to reap the benefits. As one of the best core exercises to do at home, the plank can also ...

This move, as the name suggests, combines a three-legged plank (challenging enough on its own) with a tiger curl, which involves drawing the knee under the body toward the nose. You'll work one side ...

Add Yahoo as a preferred source to see more of our stories on Google. When it comes to building core strength, crunches have fallen out of favor and the plank is now considered the gold standard.