Whether you’re a gym buff or not, you're probably familiar with the plank—that core-strengthening, endurance-building exercise that every trainer and athlete swears by. And that's because the plank is super effective and basically guaranteed to deliver results. But that doesn't mean you won't get bored with it or can't improve on the classic bodyweight exercise. This variation adapts the plank into a handstand conditioning exercise. Getting your feet off the floor and onto a wall not only ups the difficulty, but it ensures that you can't cheat engaging your core. If you don't maintain that proper tension, you could fall flat on your face. Taking the plank vertical also results in more toning of the arms and shoulders and strengthens your back and rotator cuffs. In short, this move (which takes mere minutes) will tone and build everything from your hips to your head.