This is one attraction where you can definitely control how much fun you have. Here, on the canoes, you will row your 35- foot canoe around the Rivers of America. You will have a guide or two to help you row, but you must help with the work. Unlike the Mark Twain and Columbia, these canoes are not on a track, and you go at the pace your boat determines by rowing speed. If you feel you are not getting enough exercise walking around Disneyland, then give the Canoes a shot.
I definitely recommend doing this at least once. It is fun, but if you are not used to rowing, you may be sore when done. This is a great way to see Tom Sawyer Island, and while it is work, it is also a lot of fun!