lower-limb-biomechanical-characteristics-associated-with-unplanned

Lower-Limb Biomechanical Characteristics Associated with Unplanned Gait Termination Under Different Walking Speeds

Gait termination caused by unexpected stimulus is a common occurrence in everyday life. This study presents a protocol to investigate the lower-limb ...

comparison-kinetic-characteristics-footwork-during-stroke-table

Comparison of Kinetic Characteristics of Footwork during Stroke in Table Tennis: Cross-Step and Chasse Step

The cross-step and chasse step are the basic steps of table tennis. This study presents a protocol to investigate the ground reaction force ...

Ningbo University

University of the West of Scotland

The aim of this study was to compare the effects of vibration (Vib versus noVib) during a maximal graded cycling exercise on hormonal response, precisely on cortisol (C) and testosterone (T). Twelve active males (25 ± 5yrs; 181 ± 5cm; 80.7 ± 11.1kg) randomly performed two maximal incremental cycling tests on two separate days and at the same time of the day (09:00). The protocol consisted of incremental steps of 3 min duration performed on a PowerBIKETM that induces vibration cycling. The study was a repeated measures design and participants performed the test with and without vibration. Gas exchange and heart rate (HR) were continuously assessed and blood lactate (Bla) was recorded at the end of each incremental stage. Saliva samples were collected before and immediately after the test, and analysed for (C) and (T). The results show that C and T increased in both cycling conditions; however, the C's magnitude of change was significantly higher by 83% after Vib cycling in comparison to the no Vib (p = 0.014), whereas the T's magnitude of change were not statistically different between trials (p = 0.715). Vibration induced a decrease of the T/C ratio (p = 0.046) but no significant changes were observed following noVib (p = 0.476). As a conclusion, the investigation suggests that adding mechanical vibration to cycling may potentiate a catabolic exercise-induced state, which could have potential clinical implications in rehabilitation and injury treatment. Sport experts should take this message home to carefully plan the recovery process and time during training and competitions.

Salivary endocrine response following a maximal incremental cycling protocol with local vibration.

Standing long jump (SLJ) is complicated by the challenge of motor coordination in both the upper and lower segments. This movement is also considered to be a fundamental skill in a variety of sports. In particular, SLJ is an important test index for middle school students for assessing their physical fitness levels. This assessment takes the form of a physical fitness test high school entrance examination in some countries such as China. This minireview summarizes recent studies that have investigated how to improve the standing long jump performance from different aspects which include arm motion, takeoff angle, standing posture, warming-up exercise, and handheld weight. The common study limitations, controversial knowledge, and future research direction are also discussed in detail.

How to Improve the Standing Long Jump Performance? A Mininarrative Review.

The running biomechanics of unstable shoes have been well investigated, however, little is known about how traditional neutral shoes in combination with unstable design elements and scientifically (bionic) designed shoes influence prolonged running biomechanics. The purpose of this study was to investigate biomechanical changes for a typical 5 km run and how footwear technology may affect outcomes. Sixteen healthy male recreational heel strike runners participated in this study, and completed two prolonged running sessions (neutral shoe session and bionic shoe session), with 7 to 10 days interval between sessions. A two-way repeated-measures analysis of variance (ANOVA, shoe × time) was conducted to determine any differences in joint biomechanics. Main effects for shoe type were observed at the ankle, knee and hip joints during the stance phase. In particular, decreased range of motion (ROM) was observed using the bionic shoes for all three joints, and the joint moments also had significant changes except for the frontal plane of the hip. Main effects for time were also observed at the ankle, knee and hip joints. The ROM of the sagittal plane in the knee and hip decreased post-5 km running. The reduction of ankle dorsiflexion, hip flexion, hip adduction and hip internal rotation angles were observed post-5 km running, as well as the increase of ankle eversion and external rotation, knee adduction and internal rotation angles. The kinetics also exhibited significant differences between pre-5 km running and post-5 km running. The interaction effects only existed in the ROM of the hip sagittal plane, hip adduction angle and hip internal rotation angle. The results suggested that bionic shoes could be beneficial for strengthening muscle control, enhancing postural stability and proprioceptive ability. Footwear personalization could be a solution that benefits runners, reduces injury risk and improves running performance.

Prolonged Running Using Bionic Footwear Influences Lower Limb Biomechanics.

With the development of unstable footwear, more research has focused on the advantages of this type of shoe. This type of shoe could improve the muscle function of the lower limb and prevent injury risks in dynamic situations. Therefore, the purpose of this study was to investigate differences in lower-limb kinetics and kinematics based on single-leg landing (SLL) using normal shoes (NS) and bionic shoes (BS). The study used 15 male subject volunteers (age 23.4 ± 1.14 years, height 177.6 ± 4.83cm, body weight (BW) 73.6 ± 7.02 kg). To ensure the subject standardization of the participants, there were several inclusion criteria used for selection. There were two kinds of experimental shoes used in the landing experiment to detect the change of lower limbs when a landing task was performed. Kinetics and kinematic data were collected during an SLL task, and statistical parametric mapping (SPM) analysis was used to evaluate the differences between NS and BS. We found that the flexion and extension angles of the knee ( = 0.004) and hip ( = 0.046,  = 0.018) joints, and the dorsiflexion and plantarflexion of ankle ( = 0.031) moment were significantly different in the sagittal planes. In the frontal plane, the eversion and inversion of the ankle ( = 0.016), and the abduction and adduction of knee ( = 0.017,  = 0.007) angle were found significant differences. In the horizontal plane, the external and internal rotation of hip ( = 0.036) and knee ( < 0.001,  = 0.029) moment were found significant differences, and knee angle ( = 0.043) also. According to our results, we conclude that using BS can cause bigger knee and hip flexion than NS. Also, this finding indicates that BS might be considered to reduce lower-limb injury risk during the SLL phase.

Huiyu Zhou

Faculty of Sports Science

Ningbo University

Lower-Limb Biomechanical Characteristics Associated with Unplanned Gait Termination Under Different Walking Speeds

Comparison of Kinetic Characteristics of Footwork during Stroke in Table Tennis: Cross-Step and Chasse Step