Planks are classic isometric exercises, not relying on continuous movement but instead demanding that the body maintains a certain position for an extended period of time. They don't stress the joints as much as other exercises, but they still provide a great workout.

The plank variation we chose as the best, the Straight Alternating Raise, pictured below, is also one of the most difficult to master. To balance the body in such an odd position requires a substantial activation of the trunk muscles and a continuously fine-tuned cooperation among different muscle groups.


Lumbar Spine Stretches