Surf while pregnant?!

Ok well I'm sure about every single person is going to freak out at that question and call me an idiot. 
But I might be pregnant, and am THRILLED but to be honest am sad about all the extreme sports I may miss out on as summer approaches. I love rock climbing and paddle boarding and jet skiing and cliff jumping. I feel like pregnant people are told to basically just sit down besides moderate exercise- but wait!- only 30 minutes a day or you can risk your baby's health! 
I am not asking for people to call me an idiot, I'm looking for encouragement on what I CAN enjoy if in pregnant! Surely women for hundreds of years still lived their day to day lives lifting and pushing their limits even though pregnant! We live in such a cautious world, but I do of course want to make sure the baby is safe if I'm pregnant!