Synchronized skating is a unique and growing discipline of figure skating characterized by teams of 12 to 20 skaters performing together on the ice a routine of complex formations and intricate transitions. Synchronized skaters require the team skills and unison of pair skaters and ice dancers and the athleticism and artistry of singles skaters to perform difficult step sequences at high speeds, all while linked to the skaters next to them. The synchronized discipline offers opportunities for skaters to train and compete as part of a team and now represents the largest competitive discipline within U.S. Figure Skating (USFS), the national governing body of figure skating in the United States. While competitive singles skaters often leave the sport during high school, synchronized skating has become an important avenue for USFS membership retention by providing opportunities to join high school-aged and collegiate teams (34). As the popularity of the sport increases, more synchronized skaters will seek care in sports medicine clinics for evaluation and treatment of injuries sustained during participation. This review will address the structure and demands of the sport, as well as common injuries and medical conditions that affect synchronized skaters to better equip sports medicine providers to care for these athletes.
A brief history
Synchronized skating has grown from its roots in the group performances and chorus lines included in ice skating carnivals and traveling ice shows popular in the 1930s and 1940s into a competitive sport with worldwide participation (14). In 1954, Dr. Richard Porter drew upon the popularity of ice shows and formed the first synchronized skating team at the University of Michigan to provide entertainment between periods at hockey games (33). As more figure skating clubs organized teams and began competing in the late 1970s, USFS recognized synchronized skating as a new discipline of figure skating and sanctioned the first U.S. Synchronized Team Skating Championships in 1984. The sport of synchronized skating has enjoyed tremendous growth over the past 20 years, with more than 9,000 athletes competing on 579 teams during the 2012 to 2013 season. While men are permitted to compete in synchronized skating, teams are composed primarily of women.
Popularity of the sport also has grown internationally and earned recognition in 1994 from the International Skating Union (ISU), the international governing body of both speed skating and figure skating. The first ISU World Synchronized Skating Championships were held in Minneapolis, MN, in 2000 with 21 teams representing 16 countries. Teams from Finland, Sweden, Canada, and the United States have dominated the world stage and consistently finish in the top five placements each season (33). With five to six international events each season, athletes who are not able to reach the international level as individual skaters have additional opportunities to be part of Team USA as a member of a synchronized team.
Structure and demands of the sport
There are currently 14 competitive levels for synchronized skating teams in the United States. Teams that compete in the Juvenile, Intermediate, Novice, Junior, Senior, Collegiate, Adult, and Masters levels may qualify for the U.S. Synchronized Team Skating Championships at one of three sectional championships. These eight USA Championship qualifying levels are skills-based and require that skaters pass specific skating tests to participate at the designated level. The remaining levels are developmental and do not advance to compete at the U.S. Championships. The Senior level is the highest competitive level with the top two finishers earning a trip to the ISU World Championships each year. Young children learning to skate have opportunities to learn team skills in the Beginner division, while the Adult division offers opportunities for the older skater to remain involved in the sport (33).
Synchronized skating competitions are judged under the same ISU Judging System as the other skating disciplines with scores that are based on the technical difficulty and performance of the programs. Competitive program elements include blocks, circles, lines, intersections, wheels, group lifts, and moves in the field. While most of the elements are performed with skaters maintaining various hand holds, the creative element of a program highlights individuals performing jumps, spins, free skating moves, or lifts seen in the other figure skating disciplines. Each element receives an execution score while the entire performance is awarded additional points for overall skating skills, musical interpretation, performance, choreography, and transitions between elements (15). Just as the other figure skating disciplines have experienced a rise in difficulty of the jumps and spins, synchronized skating teams are performing increasingly difficult programs with the hope of being designated as an Olympic Games Winter Sport in the future.
As teams progress through the competitive levels, the number of hours spent training on and off the ice increases. Internationally successful Senior teams practice up to 15 h·wk−1 with an additional 2 or 3 h of off-ice conditioning (9). In the United States, Junior and Senior teams practice on average 8 h·wk−1, while lower level teams practice between 1 and 4 h·wk−1 (35,37). Junior and Senior teams are required to perform both a technical short program and a free skate program, while all other levels compete only one free skating program. Synchronized skating teams practice much less than the average weekly volume of 30 h reported by elite singles and pair ice skaters (4,11,30); however team skaters are encouraged often to spend additional time on the ice in private lessons and individual practice sessions to improve skating skills. Additionally some young skaters compete individually in free skating competitions and as part of a synchronized skating team, thus increasing the number of hours they spend on the ice.
Injuries in synchronized skating
Several studies have investigated the incidence of injuries in traditional figure skating disciplines; however synchronized skating injuries data are lacking. To date, only one study has reported the types of injuries affecting synchronized skaters. Dubravcic-Simunjak et al. (9) conducted a survey of all athletes competing in the 2004 ISU World Synchronized Skating Championships to collect data on injuries sustained by synchronized skaters. While this is an important first study to examine injuries occurring during participation in synchronized skating, the results are limited by recall bias. It should be noted also that the skaters were surveyed during a stressful competitive event, which may limit recall of past injuries to only the most serious events. Additionally the sport of synchronized skating has evolved tremendously with skaters performing increasingly difficult elements, and the study performed 10 years ago may not reflect the current injury pattern. Future studies are needed to examine the current injury pattern in synchronized skating.
While figure skaters in the singles discipline have been shown to experience a greater proportion of injuries due to overuse mechanisms (10,11), injuries that occurred in synchronized skating were more acute in nature. In general, the injuries seen in synchronized skating are comparable to injuries sustained by pair skaters and ice dancers (10,30) and is likely due to the similarities between the competitive programs. Both ice dancers and synchronized skaters perform intricate step sequences at high speeds while maintaining close physical proximity and connections to other skaters. Senior synchronized skating teams also perform lifts, with a group of skaters lifting an athlete above shoulder height (Fig. 1) (15). Lift elements can result in significant injury if the lifted skater is dropped from a height.
With a team of 16 to 20 skaters performing a program, there is a high risk of traumatic injuries due to collisions or falls that can involve multiple skaters. Dubravcic-Simunjak et al. found that 43% of skaters had experienced an acute injury during their synchronized skating career. The lower extremity was injured most often, followed closely by the upper extremity and head injuries. Similar to pair skaters and ice dancers, synchronized skaters have a higher risk of injury to the upper extremity, head, and trunk than single skaters (5,10,11). Contusions were the most common acute injury at all body sites, followed by lacerations. Meniscus injuries and fractures also were noted to occur during synchronized skating participation (9).
The proportion of injuries from lacerations is greater for synchronized skaters than other disciplines (9) due to the high number of skaters on the ice skating in close proximity. The blade on a figure skate is made of steel with a toe pick at the front and a rocker bottom and ground to create both an inside and outside edge. The toe pick and the blade can cause lacerations if skaters collide. Physicians organizing medical care for synchronized skating competitions should be prepared with laceration repair kits.
Sports medicine professionals who provide medical coverage for synchronized skating events also should be aware that some elements pose more risk of injury than others. Acute injuries reported by synchronized skaters occur often during the intersection, block, and group lift elements (9). Extremity injuries most commonly occur during the intersection element when one part of the team passes closely through another part of the team. Skaters often approach from a backward direction and perform turns as they pass by other skaters, which increases the difficulty due to the reduced visibility. Collisions and falls at the point of intersection may result in lacerations and head injuries. The block element is composed of parallel lines of skaters moving as a unit at high speeds (Fig. 2). If one skater falls in the block formation, a domino effect may occur and cause additional skaters to fall on top of one another.
A concerning trend in synchronized skating injuries is the increasing number of head injuries found by Dubravcic-Simunjak et al. (9). Head injuries in this study included contusions, lacerations, and concussions and occurred most often during the lift element. While the authors acknowledged that recall bias may have resulted in greater reporting of recent head injuries, the complexity of group lifts (Fig. 2) has increased dramatically over the past several years and may lead to serious injury if the lifted skater is dropped. Similarly the lift in pair skating is the element with the greatest risk of serious injury (30). Further research in this area is warranted to determine the current risk of concussion and appropriate prevention measures with these increasingly difficult elements.
When evaluating a synchronized skater with insidious onset of pain, it is important to ask about relative time devoted to free skating versus team skating, as two-thirds of the overuse injuries reported by synchronized skaters occurred during their free skating career (9). Differences in training volume may be a contributing factor to the reduced frequency of overuse injuries in synchronized skating, however it also may be a function of the different skills performed in each discipline. Many of the overuse injuries seen in singles skaters are caused by repetitive jumping as skaters learn and perfect jumps of two or three revolutions. Unless the athlete is competing also in free skating competitions, synchronized skaters are affected rarely by jumping injuries such as patellar tendinopathy or Osgood-Schlatter’s disease. The more commonly reported overuse injuries in synchronized skaters are similar to ice dancers’ injuries and include shin splints, groin pain, hamstring injuries, and ankle conditions (9,10).
The specific etiologies of groin pain described by synchronized skaters have not yet been identified. Although the skating style and stance differs between synchronized skating and ice hockey, synchronized skaters may be experiencing adductor muscle strains similar to those seen in ice hockey players. Using electromyography, Chang et al. (7) demonstrated that the adductor magnus requires the greatest changes in activation magnitude and time during forward skating compared to the quadriceps, gluteus maximus, and biceps femoris. The adductor is eccentrically contracted during the push-off phase, and the magnitude of muscle activation increases with greater skating speeds. A balance between hip abduction and adduction is also important for generating power during backward skating. Relative weakness of the hip adductors compared to the hip abductors is a known risk factor for groin strains in ice hockey. Preseason training programs that include hip adductor strengthening exercises have been used in ice hockey to prevent adductor strains (32) and may have a role in reducing these injuries in figure skaters. Off-ice conditioning using a slide board also can be employed to activate the adductor muscles and has been shown to correlate with on-ice performance in collegiate synchronized skaters (2).
Hamstring injuries may be seen in synchronized skating due to repetitive hip extension during skating. Additionally hamstring strength and flexibility are necessary to perform spiral elements in which the free leg is extended maximally from the hip into an arabesque position. Skaters often try to force the free leg position beyond their natural flexibility in order to match their teammates, and this may lead to injury. While stretching is important to achieve the necessary flexibility for specific skating moves, it has not been consistently shown to reduce the incidence of sport-related hamstring injuries. Eccentric strengthening programs, however, are beneficial in both rehabilitation of injuries and prevention of reinjury (13).
Stress fractures are a common overuse injury in singles skaters but occur much less frequently in synchronized skaters (9,10,23). In a study of stress fractures in figure skaters, injuries to the metatarsal shafts occurred during preseason training and correlated with an increase in running volume. As mentioned previously, the lack of repetitive jumping in synchronized skating likely accounts for the absence of stress fractures reported by this subgroup of figure skaters. Similar to singles skaters, synchronized skaters may be at risk for stress fractures while participating in preseason conditioning programs.
Foot and ankle issues
A common site of injury in all figure skating disciplines is the foot and ankle, many of which are related to the skate. Any figure skater presenting with a foot or ankle complaint should be evaluated with her skates to evaluate for proper fit. The figure skating boot is constructed using one to four layers of leather to provide varying degrees of stiffness and has a leather sole and heel. Boots come in both stock and custom options, and some stock boots now have heat-moldable materials to improve the fit (29). In general, boots made specifically for synchronized skating are less rigid than those used by singles skaters and allow greater dorsiflexion at the ankle. The skate should fit snuggly around the heel while providing adequate room through the toe box. In a skater with foot and ankle pain, the medical history should include questions about the boot to determine the age of the boot, change in size, modifications to the boot, and use of stock or custom boots.
Tendinopathies in the ankle and foot occur at sites where the boot compresses underlying bones and tendons. Achilles tendonitis is reported by both ice dancers and synchronized skaters and occurs from repetitive plantarflexion and deep dorsiflexion at the ankle during stroking. Tenosynovitis also may result from the posterior boot rubbing over the Achilles tendon. A Haglund’s deformity, or “pump bump,” may develop at the posterior calcaneus from repetitive friction from a boot that is too wide. The first step in management of these conditions should be a trial of boot modifications to improve the fit through the heel. “Heel huggers” are foam inserts that sit on each side of the Achilles tendon to reduce friction over the tendon. Foam or gel padding also may be used at the posterior boot top to reduce pressure over the Achilles tendon (3).
The medial malleolus and the fibula at the level of the boot top are common sites for bursitis in the ankle of figure skaters. The malleolar bursa is an adventitious bursa that develops as a protective response to abnormal contact pressures and shear forces between the bony malleolus and the boot. With continued pressure and friction at this site, the bursa may enlarge and become inflamed. Malleolar bursitis can develop acutely or chronically and typically responds well to nonsurgical treatment. The first approach should be boot modification to improve the fit over the bony prominences. This can be achieved by “punching out” or stretching the specific area of the boot causing friction. Skaters also can try a doughnut-shaped pad applied around the malleolus. If boot modifications alone do not improve the condition, the bursa may be aspirated and injected with corticosteroid; however bursitis will likely recur if the poor boot fit is not addressed (6). Bursitis over the fibula at the top of the boot occurs from similar mechanisms and may form a painful soft tissue mass at the site of friction. In one series of figure skaters and snow boarders, magnetic resonance imaging of these masses demonstrated altered subcutaneous signal suggesting subcutaneous fat necrosis and fibrosis from chronic impingement (1). Treatment again is aimed at reducing the pressure and friction over the localized area of pain.
In a series of examinations of figure skaters’ feet, Davis and Litman (8) found that hypertrophy of both the tibialis anterior and posterior tibialis tendons were common but rarely painful to palpation. “Lace bite” is a tenosynovitis of the anterior tibialis and toe extensor tendons and is diagnosed when there is tenderness over these structures. This condition develops from improper or uneven lacing across the ankle. Additional padding can be added to the skate tongue to reduce pressure and friction across the tendons, and even lacing techniques should be encouraged to prevent pressure points (3).
Medical Concerns in Synchronized Skating
Female athlete triad
The Female Athlete Triad (Triad) refers to the interrelationships among energy availability with or without an eating disorder, menstrual function, and bone mineral density (BMD). Energy availability is defined as dietary energy intake minus exercise energy expenditure, or the amount of dietary energy remaining for other body functions after exercise training. If dietary intake is inadequate to meet the body’s need for exercise and other physiologic processes, reproductive function and bone formation may become suppressed, leading to oligomenorrhea or amenorrhea and low bone mineral density (22). An important long-term consequence of the Triad, if untreated, is osteoporosis and increased risk of fracture in adulthood (31). Low energy availability may result from purposefully restricting intake, from excessive exercise volume, or inadvertently if the athlete does not understand her energy needs.
Synchronized skaters are at increased risk of developing components of the Triad by the nature of participating in a lean, aesthetic sport. Athletes involved in judged sports that emphasize leanness are known to be at increased risk of low energy intake and disordered eating behaviors (18). A study of internationally competitive synchronized skaters found that the average dietary intake was approximately 1,500 kcal·d−1, or 26 kcal·kg−1·d−1, which is far below the recommended intake of 2,200 to 2,500 kcal·d−1 or 45 kg·kcal−1 for female athletes. More than half of the athletes reported dieting at the time of the study despite an average body mass index (BMI) of 21.3. Although 90% of the skaters had a BMI within the accepted normal range, two-thirds of the skaters desired a thinner body shape (37). Similarly two-thirds of collegiate synchronized skaters competing at a national championship event reported concern about their weight and use of weight control techniques (12). This high prevalence of body dissatisfaction and dieting behavior among synchronized skaters is similar to elite female figure skaters (16,38). Common weight control techniques among synchronized skaters include calorie restriction and intense daily exercise, with fewer skaters reporting purging behaviors, fasting, and use of diet pills (37).
Reproductive function is one of the early physiologic processes affected by low energy availability. As few as 5 d of restricted energy intake leads to disruption of the normal pulsatile release of luteinizing hormone from the pituitary gland. Chronic states of low energy availability may lead to functional hypothalamic amenorrhea (22). A study of menstrual status in elite and preelite and test-track figure skaters reported average age at menarche of 13.6 years, with only 5% of skaters reporting menarche after 15 years (36). Another study of female figure skaters found a similar average age at menarche of 13.7 years but reported 40% of skaters with amenorrhea or oligomenorrhea compared to none of the nonathletic controls (28). Further research is needed to investigate the relationship of the low energy intake to menstrual disturbances among synchronized skaters.
Low energy availability and reproductive suppression are intimately linked with bone health. Any reduction in bone formation during adolescence and young adulthood could result in reduced peak BMD through adulthood (22). Adolescents participating in high-impact sports have been found to have higher BMD scores than both nonathletes and athletes in low-impact sports (19). This is true among adolescent figure skaters as well, especially singles and pair skaters. Although still higher than the reference range, ice dancers had significantly decreased BMD Z-scores in the lower extremity and pelvis than skaters in the other disciplines (24,28). The lack of jumps performed by ice dancers likely explains this finding, and similar results could be expected in synchronized skaters who also do not train as singles skaters. The protective effects of high-impact activities on BMD were seen despite low dietary energy intake reported in the tested skaters (24). Adequate calcium intake and vitamin D also are important for optimal bone formation during adolescence, and several studies have found that the diets of figure skaters and synchronized skaters include only half of the recommended daily value of calcium (16,37).
Given the high prevalence of body shape dissatisfaction and dieting behaviors among synchronized skaters, sports medicine professionals caring for this population should consider screening for the presence of any component of the Triad. This is especially important for the athlete presenting with a stress fracture, as these injuries are rare in this subset of skaters. Education for individual athletes and teams regarding recommendations for adequate energy intake is important to help prevent the long-term consequences of low energy availability.
Exercise-induced asthma (EIA) is common among figure skaters with reported prevalence of 30% to 55% (20,21,26). Skaters may report cough, dyspnea, wheezing, or chest tightness following exercise. Risk factors for EIA, especially relevant to synchronized skaters, include female sex (especially in children), cold dry air, and ice rinks with fossil fuel powered resurfacing machines (17). Exercise may lead to bronchoconstriction and asthma-like symptoms through two different mechanisms. An increased ventilatory rate during exercise may cause bronchial constriction via reflex parasympathetic stimulation. Another explanation is that increased ventilation causes drying and cooling of the airways and results in the release of inflammatory mediators from bronchial mucosal cells (17). Poor air quality in indoor ice arenas due to release of toxic gases and fine and ultrafine particulate matter from ice resurfacing machines also have been shown to contribute to the development of EIA (25,27).
Athletes reporting respiratory symptoms consistent with EIA should have the diagnosis confirmed with an exercise challenge test. On-ice exercise challenge tests with spirometry may be used as an initial diagnostic test to evaluate skaters with symptoms of EIA in their usual training environment (20). If suspicion remains high despite a negative on-ice exercise challenge test, further evaluation with a Eucapnic Voluntary Hyperventilation (EVH) test may be performed. One study found that EVH was more sensitive in diagnosing EIA in figure skaters than the on-ice exercise challenge test; however some skaters only tested positive during the on-ice test (21). Skaters diagnosed with EIA should be treated with a short-acting bronchodilator prior to exercise to minimize symptoms.
Synchronized skating is a growing discipline of figure skating with popularity worldwide. Many skaters join the sport for the camaraderie and challenges of being part of a team that traditional figure skating does not offer. Sports medicine professionals caring for synchronized skaters should be prepared for acute injuries, especially lacerations and concussions due to collisions that may occur between skaters. Additionally it is important to look at the skating boot when evaluating the common foot and ankle injuries in these athletes. It is important to recognize that synchronized skaters may be at increased risk for the Female Athlete Triad by nature of competing in a judged, aesthetic, and lean sport, and these athletes should be screened for low energy availability and the resulting consequences. Synchronized skating offers a unique opportunity for skaters to remain active in the sport throughout their lifespan, and sports medicine providers with knowledge of this sport will be better able to care for these athletes.
The authors declare no conflicts of interest and do not have any financial disclosures.
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