I worry about possibly pushing myself too far too fast or just too far in general. I turn 60 later this year. I have bursitis, tendonitis and arthritis and have been prone to flare ups that sideline me; even walked with a cane for a while. That was only when I knew I would be on my feet a while and only until the flare subsided. I am hopeful that the weight was a major factor and that I will be less prone to it. I also hope that building up muscle will reduce the strain that is directly on the joints. Keeping the ball from grinding in the socket in my shoulders, for example. But like losing weight, once I am happy with the shape I am in I think I need to go into more of a maintenance mode to stay in shape and not push too hard. I might make an exception for the occasional long paddle on the SUP though. I am really enjoying that.