By Tanner Garrity An old coach of mine used to say that our most hated exercises are simply the ones where we stand most to improve. It’s a frustratingly accurate observation. If you’re dreading a specific type of machine or move, it’s likely because you know that it hurts, and it’s going to get more painful before it gets any easier. Which is why, left to our own druthers, most of us are really good at pretending the exercise never existed in the first place. Planks are my fitness boogeyman. I despise them. If a trainer tacks a 60-second hold to the end of a class, I will audibly curse. On my…