I haven't seen anyone on here talking about Triathalons. I have done 2. There are different events depending on what you are looking for. The one I did was Supersprint. It is the shortest one. At 47 and overweight it's all I could manage. However I must say that it is incredibly fun! And the training for it is great since you have to set yourself up with a run/bike/swim routine.
Before I ever tried one I went as a volunteer. It was a good way to learn how it works plus I saw that there were people like me competing. Not all superathletes. My first goal was to finish, that's it, no time goals. I think that more and more these events are accommodating ordinary people and I think that they are really growing.
Just some food for thought for anyone looking for something new to do/train for/try.