EFFECTS OF BASKETBALL SHOE ON IMPACT FORCES AND SOFT TISSUE VIBRATIONS DURING DROP JUMP AND UNEXPECTED DROP LANDING

The purpose of this study was to explore the effects of footwear on impact forces and soft tissue vibrations during drop jump and unexpected drop landings. Twelve male basketball players were instructed to wear two types of shoes to execute double-leg landings in each of 6 testing conditions, i.e. 2 landing styles × 3 landing heights, from a customized platform. Joint kinematics, ground reaction force, and soft tissue vibrations of the leg were collected simultaneously. The results indicated that a shoe intervention did not influence the characteristics of the impact force and soft tissue vibrations during active drop jumps. Contrarily, for the unexpected drop landings, the basketball shoe with strong cushioning properties can substantially reduced the peak impact forces as well as decreased the impact frequency and minimized the peak transmissibility

EFFECTS OF RUNNING HABITS ON MORPHOLOGY AND PLANTAR FLEXION TORQUE OF MEDIAL GASTROCNEMIUS-ACHILLES TENDON UNIT

This study aims to explore the effects of running habits on the morphology of gMTU (medial gastrocnemius-Achilles tendon unit) and plantar flexion torque, to reveal the adaptive changes of different running habits. Male habitual distance runners with forefoot strike pattern (FFS, n=10), male habitual distance runners with rearfoot strike pattern (RFS, n=10), and male non-runners (NR, n=10) were recruited. The Mindray M7 Super ultrasonography system was used to measure the morphological characteristics of the gMTU. A dynamometer was utilized to determine the plantar flexion torque. One-way ANOVA and Nonparametric Test were used for analysis. The significance level was set as 0.05. Significant differences between groups were detected on muscle fascicle length (FL) (p \u3c 0.05), Normalized FL (p \u3c 0.05), and pennation angle (PA) (p \u3c 0.01), while no significant difference was observed in other parameters. Specifically, the FL and Normalized FL were greater in FFS than NR (p \u3c 0.05), while the PA was smaller in FFS than NR (p \u3c 0.05). These results suggest that long-term running with FFS pattern could induce a greater contraction velocity and a more efficient force transmitting of the medial gastrocnemius (MG)

SHOE EFFECTS ON IMPACTS AND MUSCLE RESPONSES IN LOWER EXTREMITY DURING DIFFERENT LANDING TASKS

The aim of this study was to investigate the effect of basketball shoes on impact force and lower limb muscle activity during landings. Twelve male subjects were requested to wear two types of shoes to execute drop jumps and unexpected drop landings. Ground reaction forces, accelerations of the shoe heel-counter, and EMG signals of five lowerlimb muscles were collected simultaneously. During active landing, the intervention of basketball shoe did not significantly change the characteristics of impact force and muscle activity patterns. However, under the condition of related muscles were not being activated properly, the basketball shoe reduced the impacts and decreased the muscle postactivation. This potential effect of footwear may further be developed in preventing sports injury and enhancing metabolic efficiency during landings and/or when fatigued

Near-Infrared Super Resolution Imaging with Metallic Nanoshell Particle Chain Array

We propose a near-infrared super resolution imaging system without a lens or a mirror but with an array of metallic nanoshell particle chain. The imaging array can plasmonically transfer the near-field components of dipole sources in the incoherent and coherent manners and the super resolution images can be reconstructed in the output plane. By tunning the parameters of the metallic nanoshell particle, the plasmon resonance band of the isolate nanoshell particle red-shifts to the near-infrared region. The near-infrared super resolution images are obtained subsequently. We calculate the field intensity distribution at the different planes of imaging process using the finite element method and find that the array has super resolution imaging capability at near-infrared wavelengths. We also show that the image formation highly depends on the coherence of the dipole sources and the image-array distance.Comment: 15 pages, 6 figure

ACUTE EFFECTS OF FOREARM KINESIO TAPING ON MUSCLE STRENGTH AND FATIGUE IN HEALTHY TENNIS PLAYERS

The aim of this study was to explore the acute effects of Kinesio taping (KT) applied over the wrist extensors and flexors on muscle strength and endurance. Fourteen participants completed 50 consecutive maximal concentric wrist extension and flexion repetitions at 60 °/s and 210 °/s in KT, placebo taping, and no taping conditions. There was no significant KT effect on the strength output (peak moment and peak / average power). KT reduced work fatigue and induced an increased regression of torque compared to no taping at 60 °/s. These findings provide preliminary evidences suggesting that KT may not be able to modulate strength production in healthy athletes immediately, but would have a significant positive effect on muscle fatigue resistance during repeated concentric muscle actions

DO SHOE COLLAR HEIGHT INFLUENCE THE KINEMATICS AND KINETICS OF ANKLE JOINT IN SAGITTAL PLANE MOVEMENT

This study aims to investigate the effects of wearing high (HS) & low-top (LS) basketball shoes on the ankle joint kinematics, kinetics, and performance in the sagittal plane during different maneuvers. 12 subjects performed weight-bearing dorsiflexion (WB-DF) movement, drop jumps (DJ), and lay-up jumps (LU) in two shoe conditions. Wearing HS can significantly reduce ankle joint excursion in WB-DF. No significant differences were found in jumping height and kinematics between the two shoes. In LU, peak plantarflexion torque and power were significantly lower in HS. The high-top shoes adopted in this study did not restrict the ankle dorsiflexion performance during actual jumping. Thus, high shoe collar height would be applied to practical with caution of affecting the partial kinetic characteristics of the ankle joint in the sagittal plane

THE DYNAMIC CHARACTERISTICS OF THE PLANTAR PRESSURE IN THREE TYPICAL BADMINTON FOOTWORK PATTERNS

The purpose of this study was to investigate the dynamic characteristics of plantar pressure in the three-badminton footwork patterns (left-forward lunging step, LFLS, right-forward lunging step, RFLS, backward revolve to jump, BRJ). Twelve elite national-level male badminton athletes were recruited while performing the three typical footwork patterns tests in a laboratory-simulated badminton court. The results of the present study demonstrate that the normalized mean peak pressures (MPP) were significantly higher under the hallux and the 1st to 2nd metatarsals than other areas in the toe-off (TO) phase when performing the three footwork patterns. In the process of touching down (TD), both LFLS and RFLS showed significantly higher loads on the rearfoot and the lateral of the foot. Thus, the badminton players should be paying attention to modulating the load strategies on the front-foot, rear-foot, and lateral of the foot regions when performing the different footwork patterns, and select the appropriate footwear that can disperse the higher loads of the target areas to avoid excessive concentration of the plantar pressures

EFFECTS OF FOUR WEEKS OF HIGH-DEFINITION TRANSCRANIAL DIRECT CURRENT STIMULATION AND FOOT CORE EXERCISE ON FOOT SENSORIMOTOR FUNCTION

Objective: This study aimed to examine the effects of four weeks of high-definition transcranial direct current stimulation (HD-tDCS) and foot core exercise (FCE) on the foot sensorimotor function (i.e., toe flexor strength and passive ankle kinesthesia). Methods: Thirty-six participants were randomly assigned into three groups: HD-tDCS, FCE, and control group. A total of 12 training sessions was performed over 4 weeks (i.e., three sessions per week) in the laboratory. The participants in the HD-tDCS group performed HD-tDCS and the FCE group completed short foot exercise, towel curls, toe spread and squeeze, and balance board training. Foot muscle strength and passive ankle kinesthesia were assessed at baseline and post-intervention. Results: Compared with the control group, HD-tDCS induced a greater decrease in percent change in the passive kinesthesia thresholds of dorsiflexion ( 9.32%), inversion ( 25.15%), and eversion ( 21.46%). A significantly higher increase in percent change in metatarsophalangeal joint flexor strength was existed in HD-tDCS group (13.77%) and a significantly greater increase in percent change in toe flexor strength was observed in the FCE group (13.13%). Conclusion: Four weeks of high-definition transcranial direct current stimulation (HD-tDCS) can improve foot sensorimotor function and foot core exercise can only strengthen toe flexor muscles

IS THE HIGH-TOP SHOE MORE PROTECTIVE IN LANDING ON A TILTED SURFACE: A KINEMATIC AND ELECTROMYOGRAPHIC EVALUATION

The purpose of this study was to explore the effect of high-top and low-top shoes on ankle inversion kinematics and pre-landing EMG activation of ankle evertor muscles during the landing on a combined inverted and plantarflexed surface. Thirteen male subjects were instructed to wear high-top & low-top shoes to execute self-initiated drop landings in each of the 8 landing conditions, i.e. 2 shoes × 4 surface conditions, on an inverted (or combined plantarflexed) platform. Ankle inversion kinematics and the EMG from the tibialis anterior, peroneal longus, and peroneus brevis muscles were collected simultaneously. The results indicated that shoe collar heights did not influence the ankle inversion kinematics during landing. However, wearing high-top shoes resulted in a significant posterior onset time of the tibialis anterior and peroneus brevis muscles, and lowered the pre-landing EMG activation of ankle evertor muscles prior to foot contact during landing on the inverted surface