The plank and all of it’s variations are the BEST AND SAFEST ways to build core and torso rigidity. Especially when it comes to patients in pain, the ability to stay in lumbar spine neutral with load is a fantastic way to build tissue resiliency. Add in the benefit of working shoulder and scapular stabilization in the plank position (as highlighted in Episode 414), and you have a versatile exercise that can be adapted in so many ways. Depending on the set up, you can train anti-extension, anti-rotation, or even anti-sidebend.
One of the most unnoticed ways to cheat when it comes to the plank is PUTTING THE HANDS TOGETHER! When you do this, you're cheating by bringing your pectoralis muscles to the party via shoulder internal rotation. Trying to get as much stabilization in the shoulder joint (via co-contraction) as possible instead of relying on the scapular stabilizers (mainly serratus anterior). Many times, the weakest link in the system during a plank is actually the shoulder girdle, NOT the core. The body is smart; it's going to use whatever it can to hold that plank position, including the pecs.
Yes, you're probably getting a bit more subscapularis and lats involved as well with the internal rotation, but those should have already been active. If you really want to train the shoulders during a plank, try putting a superband around the wrists and work on the external rotators isometrically at the same time. Now that's a true killer! #plank #planks