Updated May 05, 2015.

We all know plank is great for strengthening your core muscles, but it can get a little boring. And nothing derails a workout routine like boredom. Keep things interesting with these variation on plank, which also have the added benefit of working different parts of your abdominals. If you do yoga at home, add these in at the end of your warm-up sequence to get yourself ready to flow. There's also an option to throw in a few arm balances just for fun.