It is a paradox of the world of winter sports that freestyle skiing, the most seemingly unstructured of the skiing disciplines, is judged almost entirely on a subjective basis. However, the Alpine and Nordic events, much more restricted in terms of technique and approach, are assessed by the most objective of measures: the clock.
Freestyle skiing can trace its roots in the rebellion against the established structure of Alpine skiing in the 1960s. There arose a movement among skiers, particularly in North America, to have a competitive ski environment that permitted far greater freedom of expression among its athletes. Freestyle skiing first grew in a cult fashion in the northeastern United States' mountains and the resorts of Quebec. The Canadian Freestyle Skiing Association was the first governing body in the nascent sport, formed in 1974. The International Olympic Committee (IOC) had been resistant to the inclusion of freestyle skiing in the Winter Olympics; the IOC expressed reservations that the sport was too dangerous. Nevertheless, the first Olympic freestyle competition was held in 1992, for both men and women, with the number of events available within the sport growing with each Olympics. Over 30 countries now have national governing bodies in freestyle skiing.
Freestyle skiing has two general types of competition, and athletes tend to specialize in one area only. Moguls competition is a series of events where the competitor descends a steep hill that has a pitch of as much as 30° and has been artificially groomed with an asymmetrical series of bumps of unequal dimensions. The snow surface for the course is packed to make the skis move with as little friction as possible. As the skiers move down the hill, they are required to execute a series of jumps, twists, and other acrobatic maneuvers. Each maneuver is scored in terms of its degree of difficulty and complexity, as well as the speed with which the jump was executed. The total time taken to cover the entire course is also a factor in the mogul scoring system.
Dual moguls events are conducted in the same fashion as single moguls, with two competitors descending side by side on the hill. Given the nature of the scoring for the jumps and other maneuvers, the first freestyler to descend the hill is not necessarily the winner of the event.
The second freestyle ski discipline is that of aerial freestyle, or aerials. Aerial events require the skier to descend a steep hill and leap from a ramp to perform a predetermined maneuver. The skier is judged by the level of difficulty of the jump, the technical execution of the jump, the quality of the landing, and artistic factors. Aerial freestylers are generally heralded as the glamour athletes in the freestyle world, as they will perform their routines in the air having left the ramp at speeds approaching 60 mph (100 km/h), with twisting body movements that may take them 50 ft (15 m) above the ground. The aerialist is required to land on a steep hill without losing balance.
Freestyle skiers do not require a high level of classic skiing ability. An ideal mogul skier will possess excellent balance, leg and core strength to successfully negotiate the moguls, and an extremely well-developed sense of body control, to complete jumps and land on the uneven mogul surface in rapid fire succession. Aerial skiers must possess similar physical attributes as those in moguls, with an additional emphasis on extremely well-developed flexibility.
The training required of a freestyle skier differs dramatically from that in which either Nordic or Alpine competitors will engage. Both forms of free-style skiing are high intensity sports, the moguls typically lasting as long as 90 seconds, and the aerial event approximately 20 seconds. The development of the athlete's anaerobic energy systems is crucial.
The range of motion required in the joints of a freestyle skier is profound. The ability to both generate the power necessary to jump explosively, coupled with making a soft landing to permit the skier to move on to the next element is essential. All freestyle skiers engage in significant stretching and flexibility training.
Freestyle skiing is a sport where simulation is an essential training aid. An athlete can practice the various aerial maneuvers contemplated in both moguls and aerials on a trampoline; the trampoline represents a very safe and cost-effective way for an athlete to work on the performance components in a warm indoor environment. In a number of countries, summer freestyle ski training sites have been constructed, using an artificial snow surface on the jumping hill, with the skier landing in a pond of water. As with the trampoline training, the athlete may practice intensively with a reduced risk of injury.