Go Climb a Rock
One of my favorite places to spend an afternoon with the girls is at my local indoor climbing gym Rocks and Ropes. It's a great way to work out and socialize too, rain or shine. You can rent the necessary equipment and if you're new to the sport a quick intro from an instructor will get you and a partner up to speed safely.
If you have any questions please ask in the comment section below and remember this is only an opinion. If you attempt to follow it you are doing so at your own risk and should have prior approval from your physician!