[2] Compared to cross-country skiing, upper body strength is more important because of double-poling needed along narrow snow trails.

Ski orienteering events are designed to test both physical strength and navigation skills of the athletes.

The map gives all information the athlete needs in order to decide which route is the fastest, including the quality and width of the tracks.

The athlete has to take hundreds of route choice decisions at high speed during every race: a slight lack of concentration for just a hundredth of a second may cost the medal.

The events take place in the natural environment, over a variety of outdoor terrains, from city parks to countryside fields, forests and mountain sides - wherever there is snow.

National teams from 35 countries are expected to participate in the next World Ski Orienteering Championships to be held in Sweden in March 2011.