A lot of the physical activity that you do in jobs like construction is at the very least being aided by machines. Power tools (whether powered by electricity or air) and heavy machinery do a lot of the work for you. I've seen some definitely unfit people who have kids. While it might be more enjoyable with better stamina and flexibility, neither of those are a requirement to pass on your genes. 50s is still better than the life expentency 100 years ago, when the worldwide average was in the 30s. "An extra thing you didn't mention...you did say that." I've been consistently employed for the last 16 years of my life (ever since I was a teenager). There was a single month when I was on furlough. I think that proves that attractiveness is not a requirement for employment. In fact, with only a couple of exceptions, what rejects me on job applications is the computer. I've had a very good success rate if I get past the computer.