Give birth before due date w/o exercise

Anyone gave birth to their firstborn naturally before their due date without doing anything special or exercising ? ? Im currently gg to 37w and scared if i dont walk enough or go up down stairs it will make my pregnancy overdue and my labour longer As i just started HL(no medical reason, gynae just gave to rest from work) mostly will be resting at home, so i wont be walking much. So am a little worried. #FTM