From The bike snob’s guide to cycling tribes
The Triathlete
While the Roadie holds the Triathlete in contempt, the truth is they share common DNA. Actually, that may explain the contempt – Jews, Christians and Muslims share both monotheism and a bunch of prophets, but that hasn’t stopped them from having their share of disagreements over the years. Specifically, the area in which the Triathlete and the Roadie are most similar is in their ability to reduce cycling to a fitness-building exercise, suck the joy from it and discard it so all that is left is a desiccated Lycra shell.
The Triathlete is one who partakes in triathlons – timed “races” in which the competitors swim, then “bike,” then run. (You should always be suspicious of people who use the word “bike” as a verb.) Many people even argue that it is inappropriate to consider a Triathlete a cyclist, since in some cases they are merely incidental cyclists who only ride because cycling happens to be part of a triathlon. If they changed the cycling leg to something else, like 10-pin bowling, they’d probably all be buying bowling balls instead of bicycles.
Many cyclists also believe that Triathletes are bad bike handlers and criticise them for being middling at three disciplines instead of exceptional at one. (If triathlons involved bowling instead of cycling, Triathletes would probably roll their balls in the wrong direction and take out half the snack bar.) As such, Triathletes are regarded with general mistrust, since their amphibious nature leads other cyclists to view them as slimy interlopers.
Why other cyclists don’t like them: They’re the three-bird roast of the cycling world.
Compatibility with other cyclists: Can occasionally mix with Roadies, like when you see a couple of pigeons hanging out with a bunch of seagulls.