The purpose of this study was to investigate the effects of insoles and additional shock absorption foam on the cushioning properties of various sport shoes with an impact testing method. Three commercial sport shoes were used in this study, and shock absorption foam (TPE5020; Vers Tech Science Co. Ltd., Taiwan) with 2-mm thickness was placed below the insole in the heel region for each shoe. Eight total impacts with potential energy ranged from 1.82 to 6.08 J were performed onto the heel region of the shoe. The order of testing conditions was first without insole, then with insole, and finally interposing the shock absorption foam for each shoe. Peak deceleration of the striker was measured with an accelerometer attached to the striker during impact. The results of this study seemed to show that the insole or additional shock absorption foam could perform its shock absorption effect well for the shoes with limited midsole cushioning. Further, our findings showed that insoles absorbed more, even up to 24–32% of impact energy under low impact energy. It seemed to indicate that insoles play a more important role in cushioning properties of sport shoes under a low impact energy condition.
Hung-Ta Chiu and Tzyy-Yuang Shiang
Oren Tirosh, Guy Orland, Alon Eliakim, Dan Nemet and Nili Steinberg
was hypothesized that the shock absorption capacity of overweight children locomotor system is reduced compared with their healthy-weight counterparts. The purpose of this study was to identify tibia to lower back attenuation in overweight children running using accelerometers fixed to the tibia and
Mohsen Shafizadeh, Nicola Theis and Keith Davids
and effective participation and training programs to be developed. Specifically, understanding foot strike patterns and related shock absorption mechanisms during RaceRunning may enhance performance and reduce the risk of potential injury. Research on running-related injuries in those without a
Enrique Alcántara, Arturo Forner, Elena Ferrús, Ana-Cruz García and José Ramiro
Impact mechanics of the human heel pad were studied using a ballistic pendulum. Young and elderly men and women took part in the experiment. Twelve parameters were used to describe heel pad properties. Analysis of variance was conducted to assess the influence of age, gender, and obesity. Heel pad properties were correlated with impact force and time to peak force in order to study impact mechanics. Maximal stiffness, peak displacement, and energy absorption were established so as to sufficiently describe impact properties of the heel pad. Age, gender, and obesity introduced significant differences in heel pad properties. Peak displacement and time to peak force increased in the elderly. Women presented a shorter time to peak force together with lower peak displacement, energy absorption, and lower maximal stiffness than men. Obese elderly showed lower impact forces, longer time to peak, and greater peak displacement than non-obese and younger participants. In addition, energy absorption was greater and maximal stiffness was lower for obese than for non-obese participants.
Oleg Verbitsky, Joseph Mizrahi, Arkady Voloshin, July Treiger and Eli Isakov
The goal of this research was to analyze the effects of fatigue on the shock waves generated by foot strike. Twenty-two subjects were instrumented with an externally attached, lightweight accelerometer placed over the tibial tuberosity. The subjects ran on a treadmill for 30 min at a speed near their anaerobic threshold. Fatigue was established when the end-tidal CO2 pressure decreased. The results indicated that approximately half of the subjects reached the fatigue state toward the end of the test. Whenever fatigue occurred, the peak acceleration was found to increase. It was thus concluded that there is a clear association between fatigue and increased heel strike–induced shock waves. These results have a significant implication for the etiology of running injuries, since shock wave attenuation has been previously reported to play an important role in preventing such injuries.
Jorge López-Fernández, Javier Sánchez-Sánchez, Jorge García-Unanue, José Luis Felipe, Enrique Colino and Leonor Gallardo
properties of both surfaces were assessed as in previous studies. 10 , 11 Shock absorption (%), vertical deformation (mm), and energy return (%) were recorded using an Advanced Artificial Athlete (Labosport, Le Mans, France), the FIFA-certified equipment for assessing these variables. 2 Each variable was
Anamaria Laudet Silva Mangubat, Janet Hanwen Zhang, Zoe Yau-Shan Chan, Aislinn Joan MacPhail, Ivan Pui-Hung Au and Roy Tsz-Hei Cheung
altered kinematic or kinetic variables, 11 vertical head accelerations have generally remained stable when running. It is then suggested that multiple parameters, that is, stride length, stride rate, footstrike patterns, and shock absorption by the tibia, adapt to maintain head stability. 9 , 10 , 12
Sarah C. Moudy, Neale A. Tillin, Amy R. Sibley and Siobhán Strike
the altered shock absorption approach observed in the intact limb (ie, reduced joint angles and powers) during the initial loading response phase of running, step/stair negotiation, and bilateral jump landing. 4 , 6 – 8 Thus, the intact limb must perform greater work to either continue forward
Christian A. Clermont, Andrew J. Pohl and Reed Ferber
accelerations. As upper body acceleration patterns has been shown to closely match ground reaction force data, 33 increases in CoM accelerations may be associated with higher loading rates, reduction in shock absorption ability, and a higher impact on the body leading to a potential risk of overuse injury. 14
Tomomasa Nakamura, Yuriko Yoshida, Hiroshi Churei, Junya Aizawa, Kenji Hirohata, Takehiro Ohmi, Shunsuke Ohji, Toshiyuki Takahashi, Mitsuhiro Enomoto, Toshiaki Ueno and Kazuyoshi Yagishita
smooth shock absorption ability of the lower limb joints, and leads to negative effects on dynamic balance control. According to the Yerkes-Dodson law, too great or too low stress for a particular task may result in impaired performance. 33 Oxendine applied this law in several sports and indicated that