Biomechanical strategies and the loads in the lower limbs during downhill walking with different inclination angles

Downhill walking places greater demands on the lower limb joints with a greater risk of falling when compared with level walking. The current study aimed to quantify the 3D joint kinematics and kinetics of the locomotor system, and their interactions with the trunk during downhill walking. Fifteen young adults walked at a self-selected pace on a 3-m walkway with slopes of 0°, 5°, 10°, and 15° while their kinematic and kinetic data were measured. A complete 3D biomechanical analysis of the locomotor system was performed on these data. The results showed that with increasing downhill angles young healthy adults increased the posterior tilt of the pelvis and lateral trunk bending towards the stance limb, as well as the peak dorsiflexor and extensor moments at the ankle and knee, respectively, during the first half of the stance phase (SP), and increased the peak moments at the hip during the second half of the SP. The associated joint forces also varied with increasing slopes over the SP. When the overall mechanical demands were considered over the SP, the angular extensor and plantarflexor impulses at the knee and ankle were found to increase linearly with increasing slopes. The current results may serve as baseline data for future studies on downhill walking, and for clinical applications in various patient groups. ? 2014 National Taiwan University.