If I can give any advice in this area in a late mid-stage career, find a way to have productive conversations with your supervisor/manager. After about a decade of working in IT, I felt burnt out and left to pursue a PhD. Pursuing a PhD was my high academic achiever's way of dealing with burnout by doing something more intellectually stimulating. But 10 years into a career in academia, the symptoms of burnout can still creep up. But I'm mature enough now to speak up and make sure that I can continue working at a sustainable pace.