You probably include planks in your workouts if you're a regular at the gym. There are many benefits to isometric exercise, namely, accessibility. Holding a simple position allows you to work your entire body, especially your abdominals. The problem is that the slightest flaw in your stance can cancel out all of your efforts. Be careful not to make the following five mistakes.Keep your back straight!For optimal 'planking,' it's important to keep your back straight. Often, in an attempt to be as straight as possible, people tend to apply too much pressure to their toes. To compensate, they then inevitably arch their back. However, you should be able to draw a straight line from your head to your toes!Do not shrug your shoulders!You should also be careful not to shrug your shoulders. It is essential to avoid having a gap between the shoulder blades. Pull your forearms down to find the right position. Do not hesitate to get help from someone who is watching you. Sometimes we feel like we're straight, when we really aren't!Don't move your head!Okay, so, planks aren't very fun. You have to wait, you can't move... and nothing's happening. But that's not a reason to move your head around, to see what is happening elsewhere. Fix a point on the ground and do hold it with your gaze!Do not bend your knees!Just like your back and shoulders, your knees have to be stay straight! Otherwise, your quads won't be engaged at all and your stance won't be balanced.Short sets are betterAlthough it might be tempting to break the world record, we're sorry to burst your bubble, you won't be able to! Instead, do short sets of 30 seconds, tops, with 10 seconds of rest. The shorter the set, the more you can focus on the position and, therefore, be efficient.To learn how to do a perfect plank, follow our coach's tutorial!