Background and Aim: Measurement of ground reaction forces (GRF) in different physical activities is linked with risk of the injuries of lower limb joints. Insole may alter the amount of these forces. The objectives of this study were to analyze the effects of<span style="font-family:;" dir="RTL" fa;="" 12pt;="" new="" roman";"="" "times="" roman";="" mitra";="" b=""> insole on GRF and time-to peak each reaction force, impulse, and loading rate during landing in normal individuals.
Material and Methods: Thirteen healthy male subjects with mean age, mass and height of (21.9±1.6years), (67.18±12.6kg), and (175.38±4.9cm), respectively, participated in this study. Using a Kistler force plates (1000Hz) we measured GRF during landing with and without shoe insole. Then, maximum GRF and their related time-to-peak, impulse and loading rate were measured. Repeated measure ANOVA was used to analyze the data. p<0.05 was considered significant.
Results: Wearing insole decreased the peak vertical GRF at the moment of contact of the heel with the ground (P=0.009), peak horizntal GRF (P=0.011) and the loading rate (P=0.01). But, the vertical impulse increased (P=0.0032).
Conclusion: Reduction of the vertical GRF and loading rate by means of insole may reduce the risk of lower extremity injuries during landing.
Keywords: One leg -landing, Ground reaction force, Impulse, Loading rate, Insole.
Received: Oct 28, 2015 Accepted: Dec 8, 2015