Bicycle racing has evolved over the course of several decades from simple road races into various forms of on- and off-road races. One of the fastest and most physically demanding types of races is a hybrid type of on- and off-road racing called cyclocross racing. Cyclocross racing involves a special type of bicycle capable of handling speed on road and traction and vibration off-road, and cyclocross courses are typically short loops and are varied in terrain and obstacles. A cyclocross race typically lasts from a half hour to an hour and features pavement, dirt, steep hills and run-ups, grass, and various other challenges for the rider to overcome.
Cyclocross bicycles look very similar to road bicycles but feature several important differences that suit the bike to the type of terrain it will be ridden on. For example, cyclocross bicycles feature knobby tires like a mountain bike, but the tire size is 700c, which is much larger than a mountain bike and similar in size to a road bicycle tire. This allows for lower rolling resistance but higher traction control in corners and on loose terrain.
Another feature common on cyclocross bicycles is a much tighter frame design than a road bike, allowing for more control off road but still allowing an aerodynamic position on road. Cyclocross bicycles feature drop-handlebars similar to those found on road bicycles. The fork of the cyclocross bicycle typically features more of a sweep –- or steeper angle –- than a road bike fork in order to provide more stability through off-road sections. Cyclocross bicycles also feature different gear ratios than a road bike. The gears are more suited toward mountain bike riding, but most cyclocross bikes try to cut the middle ground between road bike speed and the easier gearing of mountain bikes for steep climbs.
Cyclocross race courses feature obstacles such as barriers that force the rider off their bike. The rider must then shoulder their bicycle and hop over the barrier, or they can bunny-hop over the barrier if they are especially skilled. This often adds a unique feature to the bicycle race not common in other forms of racing: the need to get off and run. Because cyclocross courses can also feature run-ups –- steep hills that most riders must dismount and run up, hence the name –- the riders can spend a significant amount of time getting on and off their bicycles, depending on the course structure.
The format of a cyclocross race is quite similar to a criterium road race, in which the course is fairly short and the riders ride for a set amount of time plus a certain amount of laps; for example, riders may race for a half hour plus five laps. This format makes the race short but very intense and very fast, making bike handling a vital facet of racing successfully. Because of the demands of the cyclocross race, aerobic strength becomes vital to the racer’s training regimen and performance during the race.