Hiking- Most campsites offer beautiful hiking trails that are on or near the grounds. You can usually call or check online in advance.
Biking- Bringing along your bike is one of the most worthwhile choices you can make when it comes to getting a great workout while camping. And if you can't bring your own, many campsites offer bike rentals.
Boating- If your campsite is by a lake or river, see if you can rent row or paddle boats for a scenic workout.
Swimming- In lakes, rivers, or even pools, whether you're just splashing around in the water or if you set aside the time to swim laps, you'll get a good workout.
Outdoor games- For a fun workout, break out the traditional camping games: Frisbee, badminton, and volleyball are all great choices.
Use what you have- Get creative with the objects around you. Doing arm curls with soup cans and chopping and hauling firewood may not be your traditional workout, but they'll certainly be effective.
No equipment- There are many exercises you can do anytime and anywhere, such as push ups, crunches and jumping jacks.