An analysis of lower extremity kinematics in response to perturbations during running using statistical parametric mapping.

Investigating of locomotor disturbances are relevant in human injury and performance. Therefore, lower extremity kinematics were analysed in response to decelerative perturbations during running using statistical parametric mapping (SPM). 13 asymptomatic individuals (8 females & 5 males, 28 ± 3 years, 171 ± 9 cm, 68 ± 10 kg) completed an 8-minute running protocol with 30 one-sided perturbations (15 each side) to generate decelerative disturbances. A 3D-motion capture system was employed to record kinematic data. Joint angles of the ankle, knee, and hip in addition to stride duration, stride length and step width were calculated for leading and trailing strides. Results were analysed descriptively, followed by SPM of paired t-tests (P < 0.025). Reactively (after perturbation), perturbations caused decreased hip adduction and stride duration of the leading leg. The trailing leg reacted with ankle inversion, knee and hip flexion, hip abduction, as well as an increase in stride duration and step width (P < 0.025). In preparation for perturbation, the trailing leg reduced ankle dorsiflexion, knee flexion, hip flexion, and adduction. In summary, applied perturbations produced substantial reactive (feedback) and predictive (feedforward) responses of the lower limbs, most apparent in the trailing leg.