The duathlon is an athletic event that differs from both the biathlon and triathlon. In the biathlon, any two related or unrelated sporting events are conducted together. A biathlon could be a combination of a cross-country run and a bicycle race, a bicycle race and a swimming race, or even is used in winter sports to combine things like cross-country skiing and shooting at targets. The triathlon is an athletic contest where participants compete in three sports, most commonly biking, running, and swimming.
Definition of the duathlon is much more specific and there are three separate race sections, but only two sports. Primarily, people first run a set distance, then bike a set distance and for the final event, run another set distance. The Canadian headquartered International Triathlon Union tends to govern most formal duathlon competitions.
Standard distances for duathlon competitions may vary. In 2005, one of the larger competitions took place in London, and was a combination of a 10k (6.21 miles) run, 20k (12.42 miles) cycle and a final 5k (3.11 miles) run. The regular duathlon may occur on public streets, but tendency in recent years is to create off-road duathlons, which are sometimes called "dirty dus." Off road running and biking may add a more extreme element to these races, since people must negotiate uneven paths both in running and bicycling.
This doesn’t mean people participating in a standard duathlon are always running or biking on even ground. The Swiss event, called Powerman Zofingen, features a beginning 10k run over a hilly course and then a grueling 150K (93.2 miles) bike race. Lastly, participants finish the race by running another 30K (18.64 miles). Switzerland’s competition is considered by many athletes to be the most difficult duathlon in the world, requiring incredible stamina and strength merely to finish, and extraordinary athletic skill to win.
Depending upon the type of duathlon and the number of competitors, each race may feature divisions. A male and female division may exist because in general, men will outperform women in these events. Some duathlons also have kid’s divisions. These are usually limited to the less grueling competitions, or a kid division may create shorter distances so that kids can compete with exhausting themselves.
Another variant of this combo sport is a winter version, which does not use running or biking. Instead, skiers compete in both cross-country and freestyle races for a total win. They do have to make a stop between the two skiing forms to change into appropriate skis. The first of these official winter duathlons took place at the Nordic World Ski Championship in 2003.