100 poses Day 2 Pose 2: Forearm Plank Erin MotzOctober 2, 20192625 views100 Pose TutorialsTrending1 Comment2625 views 4 Day number 2 is Forearm Plank (everyone’s favorite, right?) This pose works not only the core and the back muscles but also the shoulders and upper back muscles! Some do these for fun, others for torture. Let’s see what you think. Enjoy!