Plank

The "Plank" and all its variants are considered among the best 5 exercises in terms of efficiency for training the central part of the torso, especially the abs, without overloading the spine as often happens with the classic Sit Up (in particular if performed with an incorrect technique). The difficulty of this exercise is not so much in the movement, as in maintaining the "in line" position for a certain length of time and voluntarily contracting torso muscles (abdominal and oblique and lumbar abdominals) at the same time. This exercise is a “MUST” for those who want to improve their abdominal muscles but want to reduce the load on their back to a minimum.