When I do planks at the gym, I can ask someone else to check my form and make sure I'm not sagging or lifting my butt up to high. But I can't always go to the gym, and then I end up doing planks at ...
Ask me to do a headstand or nearly any other yoga arm balance, and I can do it, but I cannot for the life of me stick a handstand without the help of a wall or a spotter. Image from Yoga Journal ...
I do a lot of salsa dancing and like many other dances you need to have certain muscles subconsciously and almost perpetually tense so that the dancer isn't having to remember to 'flex' all the time ...