Triathlon is a combination of swimming, running and cycling - and it's a fantastic way to learn new skills and stay in great shape.
But just how hard is it to combine three disciplines in one long distance event?
It starts with a 1500m swim. You then jump onto the bike for a 40km ride before finishing with a 10km run.
The gaps between the stages are known as transitions and these are crucial. Taking off your wetsuit and putting on your shoes can be decisive.
You don't need to do the full triathlon distance straight away.
You can try out Supersprint events (400m swim, 10km bike, 2.5km run), Sprint events (750m, 20km, 5km), or you can do just one element as part of a relay team.
If you want to get involved there are clubs, organisations and races all over the country.
Sir John Beckwith Building
Tel: 01509 226161
Fax: 01509 226165
British triathlon clubs list: