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 ...

YOU PROBABLY THINK you know how to do a plank. The ab training staple is relatively simple, after all—boiled down to the basics, all you need to do is get down on the ground and hold in place.

Plank hold test benchmarks for adults over 60, according to a certified trainer.