You apply the appropriate level of stimulus for where that person is currently and they exeperience positive growth. You apply too little stress and there is no

You apply the appropriate level of stimulus for where that person is currently and they exeperience positive growth. You apply too little stress and there is no adaptation or a reversal. If you apply too much, you get injured and go into reverse. I think this applies to any kind of challenge, be that physical like exercise, but also mental like learning, work, etc. The more honestly you can evaluate where you are and what you can currently handle, the better you'll be. Don't be lazy but don't let your ego or dreams of being a big shot lure you into biting off more than you can chew.