Cross-country mountain biking

Cross-country (XC) cycling is the most common discipline of mountain biking. Cross-country cycling became an Olympic sport in 1996 and is the only form of mountain biking practiced at the Olympics.

Cross-country cycling is defined by the terrain on which it is performed. XC courses and trails consist of a mix of rough forest paths and singletrack (also referred to as doubletrack depending on width), smooth fireroads, and even paved paths connecting other trails. Most cross-country trails are deemed "easy" or "intermediate", however, some paths can be difficult, even for experienced riders, such as the trails used during the Summer Olympic Games.

Cross-country bicycles are some of the lightest mountain bikes, typically between 7 and 16 kilograms (15 and 35 lb). They usually feature suspension forks in front and sometimes have suspension in the rear. In both the front and rear, most XC bicycles have approximately 100 millimetres (10.0 cm; 3.9 in) of suspension travel, although some riders prefer 125 to 150 millimetres (12.5 to 15.0 cm; 4.9 to 5.9 in) of travel as bicycle frame strength and technology advance. The geometry of the frames generally place the rider in a little more upright position than on a road bicycle but much less than on a downhill bike.

Bicycle helmets are often used for cross-country riding. However, XC riders only rarely wear full-face helmets and do not wear the full body "armour" employed by downhill riders. Cross-country cyclists are more prone to injuries than road cyclists; however, the injuries sustained by XC riders are usually not as severe.

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Wikipedia