Living in Bend for the past 3 years now and loving it. Road riding is OK, but the trails and gravel/fire roads are sweet! I'd recommend staying on the west side of Bend. You can rent bikes at most bike shops in town, mainly MTB. We've had friends rent from Sagebrush Cycles several times and had a good experience. All you need to know to get in great MTB or trail runs is the Phil's trails network. From the Phil's trailhead you can put together 5-50+ mile rides/runs. They're all well marked and in all the apps (like trailforks, etc.) For swimming hit Juniper Pool - $6 drop in rate. It's a 50m outdoor pool with a ton of open lap swim times. Usually set up as 2 8x25m pools but its LCM on Tu and Th. Would recommend staying in the west side of town for best access to the outdoors stuff as well as the "downtown" area with restaurants and breweries. But Bend is a pretty small place so pretty much everything is accessible. Feel free to ping me for specifics.