Ankle range of motion among surfing athletes
Australian Strength and Conditioning Association
Faculty of Health, Engineering and Science
School of Exercise and Health Sciences / Centre for Exercise and Sports Science Research
In surfing, the athlete rides a board across the wave, performing manoeuvres that require lower-body strength and power. The lower limb position on the board will range from fully flexed to completely extended, demanding full range of motion of the lower extremity joints. Furthermore, the athlete will need to produce and arrest high forces throughout this range of motion, due to the complex manoeuvres that are required to ensure success in competition. High-risk manoeuvres, such as vertical turns, aerials and tube-rides, all score high in competition, however, such tasks require high velocity change of direction, landing and compression, which may put the surfer in a vulnerable position for lower extremity joint injury unless proper development of strength and flexibility is implemented. Among all injuries in surfing, about 40% occur in the lower extremities with approximately 15-20% occurring specifically in the ankle and foot. Although only a few studies have used weight bearing ankle dorsiflexion as a measure to predict injury risk, initial evidence has shown that limited dorsiflexion range of motion (ROM) increases injury risk, suggesting that this may be an important measure for athletes, especially those using the full ROM at the ankle joint. Ankle dorsiflexion ROM can be measured in different ways, however a weight bearing assessment that has been shown to be highly reliable for both injured (ICC 0.99) and non-injured populations (ICC 0.99), and moderately reliability for a younger age group (ICC 0.83), is the knee to wall measurement (KW). Previously Hoch, et al. reported on KW measurements for 14 males and 21 females around 25 years of age. They found an average knee to wall distance of 11.9 ± 2.8 and 12.0 ± 2.8 cm for the left and right limb respectively, with the maximum score just above 17 cm. Furthermore, they did not find any statistical relationship between KW and age, limb length, height, mass or posterior talar displacement, indicating that these measures do not influence the KW score. Another study that compared ballet dancers to a control group found that the control achieved 3.8 ± 2.2 cm and the dancers 6.4 ± 2.8 cm. Since surfing manoeuvres are highly dynamic movements, surfing athletes need a large ROM in the ankle joint to be able to assume a fully compressed position. To the authors’ knowledge, there is no data published that describes the ankle ROM among surfers, and compares different groups of surfers. Whether ankle ROM is an important measure for surfing athletes to perform at their highest level and to avoid ankle injury is yet to be determined. However, this study aimed to describe the ankle ROM among different groups of surfers, compare the ankle ROM to previously published data and surfers with a previous ankle injury, and last compare the weight bearing ankle dorsiflexion ROM test measured with two different systems (KW and inertial sensors).