Variability, or how a task changes across trials, may reveal differences between athletes of differing skill levels. The purpose of this study was to examine trunk and lower extremity (LE) single joint kinematic variability and inter-segmental coordination variability in dancers and non-dancers during bipedal vertical dance jumps (sautés). Twenty healthy females, ten with no formal dance training and ten professional dancers, performed 20 consecutive sautés. Single joint kinematic variability was assessed using mean standard deviation of angular displacement, and inter-segmental coordination variability was assessed using angular deviation of the coupling angle between segments. Within the context of the standard error of measure, there was no difference in single joint kinematic variability between dancers and non-dancers. Inter-segmental coordination variability in the trunk was higher than variability in LE couplings for both groups. Dancers had lower inter-segmental coordination variability than non-dancers for LE sagittal, frontal and transverse plane couplings and sagittal plane trunk couplings. Trunk adjustments may be important for successful performance, but lower inter-segmental coordination variability in expert dancers indicates a higher level of control. Trunk coordination and postural control may be important factors to investigate in skilled athletes.
Jarvis DN, Armour Smith J, Kulig K. Trunk coordination in dancers and non-dancers. Journal of Applied Biomechanics. 2014; 30 (4): 547-554.