Kinematic Sequencing Differences Between Dancers and Team-Sport Athletes During Jumping and Landing
Karl Orishimo1, Ian Kremenic1, Evangelos Pappas2, Marshall Hagins3, Marijeanne Liederbach4
The propulsive phase of a countermovement jump is characterized by a proximal-to-distal transfer of joint velocities, with peak hip extension velocity preceding peak knee extension velocity, which in turn precedes peak plantarflexion velocity. During landing, this follows a distal-to-proximal pattern. Due to their extensive training in jumping and landing activities, dancers are considered experts in these tasks and would be expected to demonstrate optimal kinematic sequences.
PURPOSE: To compare lower extremity kinematic sequence during single-leg countermovement jumps and drop-landings between male and female dancers and team-sport athletes.
METHODS: Forty dancers (20M, 20F) and forty collegiate athletes (20M, 20F) performed single-leg countermovement jumps to 50% of their maximum jump height (takeoff analysis) and drop-landings from a 30 cm platform (landing analysis). Kinematics were measured with eight infrared cameras and 22 reflective markers. For each subject, the velocity profile of each joint was normalized to the maximum velocity achieved by that joint during each activity. Repeated-measures ANOVA were used to compare the timing of peak joint velocities.
RESULTS: Distinct proximal-to-distal and distal-to-proximal kinematic sequences were evident for takeoff and landing in 85% of the dancers (34 of 40), but only in 50% of athletes (20 of 40) (P = 0.0016). During takeoff, the time from peak hip velocity to peak knee velocity was longer in female dancers compared to female athletes (17±10 msec vs. 11±7 msec, P = 0.04). During landing, the time from peak ankle velocity to peak knee velocity was longer in female dancers compared to female athletes (28±6 msec vs. 21±6 msec, P = 0.002). There were no differences for males.
CONCLUSIONS: Dancers were more likely than athletes to demonstrate correct kinematic sequence, likely because of their intense training in jumping aesthetics. During takeoff, female dancers appear to utilize their hips more effectively than female athletes to generate initial propulsion. Female dancers also appear to utilize their ankles more effectively to absorb the initial impact of landing. The more rapid transfer of joint velocities, from the hip to the knee in takeoff, and from the ankle to the knee in landing, for female athletes versus dancers indicates a knee-dominant strategy.
1 Nicholas Institute of Sports Medicine and Athletic Trauma, North Shore LIJ Lenox Hill Hospital, New York, NY.
2 University of Sydney, Discipline of Physiotherapy, Lidcombe, New South Wales, Australia
2 Long Island University Division of Physical Therapy, Brooklyn, NY.
3 Harkness Center for Dance Injuries, NYU Langone Medical Center Hospital for Joint Diseases, New York, NY.
(Sponsor: Malachy P McHugh, FACSM)