You dont specify what kind of back problems, John, so Ill have to wing it a little. But I take it that in general youre not comfortable sitting in confined positions, or when you cant move around much. Kayaks pose some challenges here, as they tend to be a little on the cramped side (which is desirable, as a snug fit helps you control the boat), and they force you into a sort of legs-straight-out position.
Ocean Kayak Prowler 13

Still, there are some options. One is to get a sit-on-top kayak. These have the obvious advantage of a roomy, spacious sitting arealiterally, you sit on top of the kayak (well, in a small depression, but not in an enclosed cockpit). That makes the boat easy to get into and out of, and offers a much less confining sitting area. You can shift around more and hopefully be more comfortable. A good example of such a boat is the Ocean Kayak Prowler 13 ($769; www.oceankayak.com). Its a good-sized boat13 feet in lengthso its big enough for a long day trip, with room for extras such as lunch, clothing, and a camera. It comes with a backrest, of course, but for $65 you can add an Ocean Kayak Comfort Pro backrest thats taller and offers more support. Might be a useful option for you.
You might also look at some of the sit inside” kayaks that have oversized cockpits, again because I think having extra room will be advantageous. Daggers Echo 12 ($700; www.dagger.com) is such a boata comfortable, stable kayak that has an extra-roomy cockpit thats easy to get into and out of and doesnt feel like you just slid into a plastic tube. No optional seat with the Echo, but you should be able to find a comfortable position.
As for over-55 resources, I should think thered be plenty in your area. From what I understand, the area around Sherborn (located 18 miles southwest of Boston) has all sorts of open spaces and hiking trails. There might well be a chapter of the Appalachian Mountain Club (www.outdoors.org) in your area. And, if so, theyre sure to organize regular hikes for a variety of fitness levels. I dunno how your back would hold up on a bicycle, but the same thing would apply. You could find a club (inquire at your local bike shop) and go from there. You might consider a recumbent bike, sort of the two-wheeled equivalent of a sit-on-top kayak, as theyre much easier on ones back than a traditional bike.
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