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INTER-LIMB COORDINATION ACCORDING TO THE USE OF FOOTSTRAP DURING PUMPING IN WINDSURFER: A SINGLE SUBJECT PILOT STUDY
Get PDFThe purpose of this study was to quantify limb coordination patterns according to the use of footstraps when pumping in windsurfer. We hypothesized that pumping would show different coordination patterns depending on footstrap use. One windsurfer participated in the experiment and performed two types of pumping (footstrap and non-footstrap). Inertial measurement unit (IMU) sensors were using for obtain kinematic data for the elbow, hip, and knee joints. The continuous relative phase angles of elbow-knee and hip-elbow were calculated using kinematic data obtained from IMU sensors. This study showed that limb coordination patterns differed depending on use footstraps. These results can be used as background information for designing experiments to understand pumping movements in windsurfing
COMPARING WORK AND RATE OF FORCE DEVELOPMENT DURING PROPULSIVE PHASE AS PILOT STUDY IN EXPLOSIVE MOVEMENTS
Get PDFThis is a pilot study that aims to compare work and rate of force development (RFD) during the propulsive phase in loaded and unloaded conditions across countermovement jump (CMJ), jump shrug (JS), and power clean (PC) exercises. University students with regular exercise habits were recruited. The motion capture system and force plates were used for biomechanical analysis. The positive work during the propulsive phase significantly differs in CMJ, JS, and PC (
LOWER LIMB JOINT WORK DURING COUNTERMOVEMENT JUMPS IN CHILDREN WITH CHARCOT-MARIE-TOOTH TYPE 1A
Get PDFThe purpose of this study was to identify lower limb joint power and work in countermovement jumps (CMJ) in children with Charcot-Marie-Tooth type 1A (CMT1A). Therefore, previously collected CMJ data of seven children with CMT1A were compared to seven age- and sex-matched typically developing children (TDC). We focused on the parameters angles, moments, power and work of the hip, knee and ankle joint. In the knee and ankle joints, significantly lower values of power, positive work, and total work were found in children with CMT1A. Furthermore, a lower percentage of knee and ankle contributions to total work was found when compared with TDC. This study might be an addition to previous findings concerning reduced jumping performance in patients with CMT and might therefore provide further information for therapeutic and training plans
USING PARTICIPANT DESCRIPTIVE CHARACTERISTICS, HEART RATE AND INERTIAL SENSORS TO ESTIMATE RUNNING ECONOMY
Get PDFIn this study, we aimed to develop a machine learning algorithm to estimate running economy. Inertial sensor, heart rate and participant descriptive characteristics were used to estimate running economy by training and comparing five different machine learning models. Fourteen subjects performed a VO2max running test on a treadmill with four-minute stages. Submaximal running speeds (lactate level \u3c 4 mmol/l) were used to train the models. The best-performing model was a k-nearest neighbour regressor, which achieved average root mean square error of 0.097 ± 0.059 kcal/kg/km and average mean absolute percentage error of 8.7 ± 5.8 % compared to ground truth running economy data. Despite reasonably accurate running economy estimates, the model is currently not very generalisable, probably due to the small dataset used for training
LEARNING BIOMECHANICS: DEJA-VU ALL OVER AGAIN
Get PDFThis article reviews the physics education research (PER) and scholarship of teaching and learning (SoTL) on introductory biomechanics. Many sport and exercise science students fear and dislike biomechanics, so faculty have shared their teaching ideas at many conferences, with a smaller number reporting research on the efficacy of these ideas. These is a large body of PER that consistently report active learning (AL) is twice as effective or more for learning Newtonian mechanics than lectures. Biomechanics scholars have followed this work with specialized standardized tests, finding similar benefits of AL for all students in-person and in online instruction. SoTL research is important to the real-world impact of sports and exercise biomechanics and there is a need for better understanding of specific AL exercises, dosage, and how students interact with them
THE SEXES EXHIBITED SIMILAR PATTERNS OF UPPER TRAPEZIUS EXCITATION DISTRIBUTION AT REST AND WITH FATIGUE DURING REPEATED ARM ELEVATION
Get PDFFemales experience more shoulder pathology compared to males, which is partly attributed to differences in muscle excitation between the sexes. We determined if upper trapezius (UT) excitation distribution differed at rested and fatigue at three tertiles of shoulder flexion. Twenty-eight participants completed a repeated arm elevation task to volitional fatigue while holding a load relative to 30% of their maximum isometric shoulder flexion force while high density electromyography was collected from the UT. Statistical parametric mapping t-tests between males and females excitation map for each tertile at rested and fatigue revealed that UT excitation differed in 168 pixels (~43% of the map) between the sexes during tertile 2 at rested, with no other significance differences. Further research is needed to understand females’ higher risk for shoulder pathology
DYNAMIC VERSUS SELF-PROPRIOCEPTIVE NEUROMUSCULAR FACILITATION STRETCHING ON VERTICAL JUMP PERFORMANCE
Get PDFMost warm-up routines are performed without the help from coaches or trainers. Warm-up routines often include a stretching component. The purpose of this study was to determine whether self-PNF is comparable to dynamic stretching prior to performing a vertical jump. Twelve participants performed pre- and post-intervention vertical jumps in random order and at least 48 hours apart. Interventions included dynamic stretching, self-PNF and a control. No significant differences (p \u3e 0.05) were found between or pre- versus post-intervention for vertical jump height and peak force. However, there was a slight increase in both measures for post-dynamic stretching and a slight decrease post-self-PNF. Coaches should continue to use dynamic stretching and avoid self-PNF, especially prior to an anaerobic-power event
THE EFFECT OF UP AND DOWNHILL SLOPES ON TECHNIQUE AND PERFORMANCE IN GOLF
Get PDFThe purpose of this study was to quantify differences in key variables suggested from golf coaching literature, when playing from uphill and downhill slopes. Forty-five golfers in a mid and low-handicap group hit shots from flat, uphill, and downhill slopes, whilst their body and club movements were captured, and the ball flight was calculated. Most findings concurred with much of the coaching advice, which is now quantified scientifically, whilst other variables seemed to contradict the advice, such as aim direction. Golfers should not necessarily follow all coaching advice from the coaching literature, and should instead inspect their own data with the help of a coach to find the best individualised approach to playing from up and downhill slopes
ANALYSIS OF PROACTIVE, STATIC AND DYNAMIC UNIPEDAL BALANCE IN YOUNG GYMNASTS DURING ADOLESCENCE
Get PDFThe aims of this study were to evaluate the effect of age in young acrobatic gymnasts on performance and asymmetry between lower limbs in proactive, static, and dynamic balance. 37 acrobatic gymnasts (31 females and 6 males) were divided in Early (EA, n=10), Middle (MA, n=16), and Late (EL, n=11) adolescence according to peak height velocity. Three types of unipedal balance tests were applied and normalised relative to participants height: Y-Balance Test, single leg stance test (centre of pressure measurements with a force platform), time to stabilization after single leg landing test. EA gymnasts had worse static balance compared to MA and LA, and showed greater asymmetry in proactive balance between both legs compared to MA. These results must be considered given the high demands of static and proactive balance in early adolescence acrobatic gymnasts
INTRA-INDIVIDUAL VARIATION IN THE JUMP SMASH FOR 19 MALAYSIAN ELITE BADMINTON PLAYERS
Get PDFThe badminton jump smash is a key skill that is crucial for winning rallies in badminton, but players can have substantial variations in smash performance. In this study the intra-individual variation in the badminton jump smash was investigated. Twenty-five jump smashes were recorded using a 3D motion capture system for 19 elite badminton players with the three fastest and three slowest jump smashes per participant selected, analysed and categorised into FAST and SLOW groups (95.0 ± 3.6 m×s-1 and 85.8 ± 5.8m×s-1). Post impact shuttlecock speed, racket head speed at contact and longitudinal impact location were found to have a significant difference between the two groups. To achieve a consistent smash coaches should encourage a consistent fast racket head speed and positioning of the racket relative to the shuttlecock at impact in their training strategies