The exercise I prefer in the summer is walking on the beach at dusk. Bring along a little bug spray, and walk to a spot where you can put a blanket down and watch the sunset. Then find your way back under the stars. It is exercise, but also a great adventure with a friend or time to meditate solo.
The image in this post is one I took in 2009 at the pier in Surf City, North Carolina where I currently live and work.