Everyone is different the key part is to listen to your body and not push yourself too much when flaring. Doing what you love is important; you will just have to get really creative about
it sometimes.
I am one of the UCers where intensive exercise can induce flare ups. I also cannot do moderate to intense exercise during a flare; it can make it worse. I had a particularly bad flare when I was training for a marathon after one long run (it hit me within 24 hours). After that I was able to do shorter runs no problem.
Now I can't run due to severe GERD, but you should be okay once you get the flare under control
I've learned to love hiking, biking and other less intensive activities and I don't feel that it's a loss.