Since most bodybuilding sessions are under an hour with rest in between sets you'll probably don't need carbs pre workout. Post workout you can have some to replenish the reserves. If you're too low on carbs you'll notice muscle fatigue setting in way faster if you're too high you'll notice with your BG levels. There are some athletes that are LCHF but not many research has been done on the subject, most of them seem to do fine though. If you have a use for the carbs they're not that bad if you're overdoing them they'll start messing up your BG, when not diabetic it's not that harmful but when you are you need to pay attention obviously. It's a bit more tricky but not impossible to find the right balance, and there's something to say about higher fat too. Whichever way you go checking your BG before and after workouts is a good thing to do, couple of hours after too. I find that hypertrophy based workouts have a greater effect on my BG than strength based workouts (because of the rep ranges most likely).