Acute Effects of Midsole Bending Stiffness on Lower Extremity Biomechanics during Layup Jumps

Abstract

Purpose: This study aims to investigate the acute effects of shoe midsole stiffness on the joint biomechanics of the lower extremities during specific basketball movements. Methods: Thirty participants wearing stiff midsole shoes (SS) and control shoes (CS) performed layup jumps (LJs) while the kinematics and ground reaction forces were simultaneously collected via the Vicon motion capture system and Kistler force plates. Furthermore, the joint angles, range of motion (ROM), joint power, joint energy, and jump height were calculated. Results: No significant differences were observed between SS and CS conditions for both jump height and the metatarsophalangeal (MTP) joint biomechanics except that the minimum angular velocity of the MTP joint was significantly lower in SS the condition. However, the ROM in the ankle joint was significantly greater in the SS condition than in the CS condition (p < 0.05). Additionally, the maximum plantarflexion power, energy absorption (EA), and energy generation (EG) in the ankle joint were significantly greater in the SS condition than in the CS condition (p < 0.05). Compared with the CS condition, jump height in the SS condition did not increase. Conclusion: During a single LJ, the longitudinal midsole stiffness did not influence the jump height and MTP joint biomechanical patterns but significantly increased the maximum power, EA, and EG during the push-off phase of the ankle joint. These preliminary results indicate that wearing SS could change the ankle joint mechanical patterns by modulating the lower extremity kinetic chain, and may enhance muscle strength in the ankle.

Shoe Bending Stiffness Influence on Lower Extremity Energetics in Consecutive Jump Take-Off

“…Through this experiment and combined with previous studies on vertical jumps [ 12 , 22 ], the effect of shoe bending stiffness on the upward jump is concentrated on the MTP joints, and the influence on the hip and knee joints is relatively small.…”

“…The authors suggested that the stiffer shoes reduce the energy absorbed from the MTP joint, and the rest of energy would improve about 3.5 cm height (70 kg mass body). Some other studies also found no significant differences between stiff and control conditions in lay-up movement [ 22 ] and running vertical jumps [ 17 ]. One possible reason is that the actual difference in stiffness between the two shoes is too small to generate the significant improvement showed in Stefanyshyn and Nigg's study (energy improvement = mass × height × gravity = 70 × 3.5/100 × 9.81); the experiment of Stefanyshyn and Nigg's [ 12 ] research increased the forefoot stiffness from 0.04 Nm/° to 0.25 Nm/°; our conditions only compared the difference between 0.297 Nm/° and 0.366 Nm/°, so it is not difficult to understand: there are significant differences in MTP joint work, but insufficient changes at the MTP joint to significantly alter athletic performance.…”

“…From the test results, there is no significant difference in the kinematics and kinetics of the hip, knee, and ankle joints, which does not agree with some literatures. The results of Zhu and colleagues [ 22 ] showed that a stiff midsole significantly improved ankle RoM, maximum power, energy absorbed, and energy produced. Another study also found that stiff shoes can regulate the biomechanical properties of the ankle joint [ 38 ].…”

“…Participants warm up with five-minute treadmill run at a personal comfortable pace, followed by self-administrated stretches and some jumps [ 22 ].…”

The Effect of Fatigue on Lower Limb Joint Stiffness at Different Walking Speeds

“…The Vicon 3D analysis system (Vicon Metrics Ltd., Oxford, UK) with eight infrared cameras was utilized to acquire kinematic data of the lower limbs at 200 Hz. Twenty-five reflex markers (9.00 mm in diameter) were used to designate the pelvis, thigh, shank, forefoot, and rearfoot segments ( Figure 1 ) [ 44 ]. Vertical ground reaction forces were measured using AMTI force plates (AMTI, Watertown, MA, USA) at 1000 Hz.…”