Exercising while pregnant?

Bri 🇺🇸 • Expecting our 1st baby this November. Can`t wait to meet her❤️ ICP mommy • #itchybaby
So my dr said I'm good to go and pretty do what I've been doing when I'm at the gym except for anything that has to do with jumping. 
I asked one of the trainers if he knew any good prenatal exercises and he said no but that a client of his told him that her heart rate couldn't go higher than 145bpm. 
My dr never said anything about heart rate needing to stay below a certain amount. Just curious if any you know anything about this? Just want to make sure I'm not putting my baby or myself at risk. This is all new to me haha.