As an older athlete, you have had more life experience than the younger competitors. Perhaps you are a successful businessperson, chief executive of your own company, or a partner in a law firm. You are used to winning simply by applying yourself and working hard.
Unless you have a strong background in athletics, don't expect to scale the heights in your first stab at a triathlon. All the determination you can muster will not necessarily get your new-to-athletics body in shape to win your first time out.
Set your sights on a shorter distance for your triathlon, and be happy to finish. Don't worry about where you place, and don't try to compete with the younger athletes.
Don't turn your nose up at a “baby” triathlon such as a sprint distance aimed at newbies. You don't have to conquer Mount Everest on your first attempt to be successful. There is no shame in thinking small for your debut. You don't even know for sure that the three-sport event is right for you.
You can be more ambitious next time out if your first shot goes well. It's okay to dream of the Ironman Triathlon, but start with the sprint version.
As an older athlete just starting to train for a triathlon, you will enjoy your preparation more if you can find a few other aspiring athletes roughly your own age. You will relate to them better, and the training pace will be more comfortable for all of you.
If you are returning to athletics in your forties or fifties after a long layoff because of career and family issues, don't get caught in the trap of trying to regain past glory. Your body simply won't do what it once did, and perhaps you don't remember the past as well as you think you do. This thought, “The older I get, the better I was,” might apply to you. Be realistic.
If you are a nonathlete, don't think about your first triathlon unless you can give yourself twelve weeks to get ready for it. If you don't have a good base of running and biking, make that sixteen weeks.
It is not realistic to think you can undergo the stress of the training and the race without first getting your body used to it. That process will take longer with older athletes, especially those who have not been active in years.
You are to be commended for daring to compete in a triathlon. You will enjoy the training and the actual event more if you prepare properly.