Life begins at 35?
When it comes to running, even if you begin much later in life, you apparently reach mastery at age 35 years. The bad news is that you begin to see your name beside an age category in race results, so if you're minded to hide your age from friends and colleagues, you're scuppered. The good news is that (a) you don't suddenly enter decrepitude and (b) there is a host of new personal goal / competitive opportunities in the form of masters competitions, age category prizes and performance age grading.
The British Masters Athletic Federation and Irish Masters Athletics cooperate to organise competitions between athletes of these island nations.
For some, but certainly not all, events you'll need to pre-register with your relevant national or regional masters athletics association. For certain running disciplines, such as cross country, you even have the chance to earn a place on a national team.
Want to compete on the world stage? Often all you need to do is register for your event and pay your way.
Next: Age Grading