A: There is a general rule for physical activity: you should be able to do that activity again after finishing it. So, if after three to four hours of pickle-ball you feel like you’re just done for the day and need to spend the rest of the day in bed, that's probably too much. If after three to four hours of pickleball, you feel like you could do another three to four hours of pickleball, then that's a good measure indicating that it’s the right amount of activity for you. I wonder if four hours is kind of where you feel maxed out; cutting down to two hours a day might be a better option. It seems to be a low impact sport, so I think that is generally going to be good, but it really depends on you.
I've had some people for whom even just walking around the block was too much. When I was pregnant, that was certainly the case for me too. Therefore, I would encourage you to check in with your body and do the test that way.