The plank is an isometric core strength exercise that involves maintaining a position for the maximum possible time. The forearm plank is what most people consider to be a standard plank.
It builds strength in our core, upper and lower body so it´s a good full body workout. We do not need any equipment to perform this exercise, and it also improves flexibility by stretching muscles and will improve posture if performed regularly.
The plank works almost every main muscle: deltoids, biceps, triceps, obliques, rectus abdominis, erector spinae, latissimus dorsi, pectoralis major, gluteus maximus, quadriceps, hamstrings, gastrocnemius.