The Plank---Proper Form
Ohhhhhh, so you can plank for 3 minutes, huh? I'm going to go out on a limb and tell you that if you think you can, you aren't doing it right. The PLANK is a full body exercise that requires you to put in a ton of effort--- YOU make the work.
The cool thing? If you do it right, you don't have to sit there for three minutes! Do it right, and then move on and do something else. Save yourself the three min!