After briefly dabbling with climbing in my younger years (mid-1970's), I pretty much stopped as other pastimes kept me busy. In all honestly, I wasn't very good either. At the time, it seemed like an endless succession of one-armed pull-ups, and frankly, I never was very good at those. A few years ago ( was 45 at the time), a climbing wall/gym opened up in my town (I’m not in the Boston area, so I can’t help you in that regard), and I thought it would be fun to expose my grade-school age kids to the sport. Of course, that meant that dad had to get back into it as well. What a blast! While muscling my way up the wall is clearly no longer feasible (funny things happen to the old strength:weight ratio as years go by!), I amaze myself with some of the moves I can do, with practice. It also has proven to be something which is fun to do with my kids, although I am much more confident belaying them than they are belaying me – they are only 10 and 7. It is very hard to get a kick of adrenaline when you have only a hour to blow in suburbia, but this really fits the bill. Climbing walls does seem more like vertical tai chi than rock climbing, however. The above caveats on converting climbing wall skills to outdoor skills are well taken, but I can relate that it has given me a much better feel for my limitations, and more importantly , for my strengths. I have no delusions of going out to climb El Capitan, but it has given me the skills and confidence to take on more challenging scrambles and slides than I might have done in the past, thus enhancing my already numerous outdoor activities. Go for it, and enjoy! There are a lot worse things you could be doing with your mid-life crisis.