Abstract:
In complex movements, centre of mass translation is achieved
through effective joint and segment rotations. Understanding
segment organisation and coordination is therefore paramount to
understanding technique. This study sought to comprehensively
describe inter- and intra-limb coordination and assess step-to-step
changes and between-individual variation in coordination during
initial sprint acceleration. Twenty-one highly trained to world class
male (100 m PB 9.89-11.15 s) and female (100 m PB:11.46-12.14 s)
sprinters completed sprint trials of at least 20 m from which sagittal
plane kinematics were obtained for the first four steps using inertial
measurement units (200 Hz). Thigh-thigh, trunk-shank and shankfoot
coordination was assessed using a modified vector coding and
segment dominancy approach. Common coordination patterns
emerged for all segment couplings across sexes and performance
levels, suggesting strong task constraints. Between-individual
variation in inter-limb thigh coordination was highest in early flight,
while trunk-shank and shank-foot variation was highest in late flight,
with a second peak in late stance for the trunk-shank coupling. There
were clear step-to-step changes in coordination, with step 1 being
distinctly different to subsequent steps. The results demonstrate that
inter-limb coordination is primarily anti-phase and trailing leg
dominant while ankle motion in flight and late stance appears to be
primarily driven by the foot.
