Research Paper: Effectiveness of Joint Stiffness and Power Alternations in Different Shoe Insole Hardness on Injury Prevention During Jump-landing

Purpose: Studies on how the shoe insole hardness regulate joint stiffness and transfer energy in the lower extremity during jump landing are scarce. The current study aimed to determine the effectiveness of shoe insole changes in joint power and stiffness during landing from jumps. Methods: Fifteen healthy male athletes volunteered to perform jump-landing in various shoe insole conditions. Kinematics and kinetics data were examined to calculate joint stiffness and peak negative power (absorbing power). Results: The shoe insole hardness significantly affected ankle joint stiffness (P≤0.05). Furthermore, enhanced shoe inserts hardness increased ankle joint stiffness. Moreover, soft insole significantly increased negative peak power, compared to the hard insole condition (P=0.01). Conclusion: Increasing the shoe insert hardness can higher affect the distal ankle joint, compared to the proximal joints. However, landing with soft shoe insoles increased the negative joint power during landing; it implied neuromuscular adaptation in response to the impact signals and elevated eccentric force by the knee extensors.