What NOT to do when planking!

What NOT to do when planking!

Performing a Plank is a simple but effective bodyweight exercise that develops strength primarily in the core—the muscles that connect the upper and lower body—as well as the shoulders, arms, and glutes.Quite often though as a trainer I see some very common mistakes....
Try these great Plank variations!

Try these great Plank variations!

1. The classic plank2. Not quite there yet? If you are unable to hold the classic plank for more than 20 seconds, scale back to this version, Plank with Straight Arms:Rotate your arms so that the crease in your elbow is facing directly ahead.3. Plank with a dynamic...