Ah that's why I didn't get the joke. Boulderers don't have large triceps or deltoids...to the extant that arms are used in bouldering, it is in pulling activit

Ah that's why I didn't get the joke. Boulderers don't have large triceps or deltoids...to the extant that arms are used in bouldering, it is in pulling activities that develop the back, biceps, and forearms, not the deltoids or triceps. You only get large delts and tris without developing other muscles by doing excessively long static planks.