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RUNNERS SACRIFICE ECONOMY FOR STABILITY AND TRAUMATIC INJURY PREVENTION WHEN FACED WITH SUDDEN, SLIP-LIKE PERTURBATIONS
Get PDFWe investigated the trade-off between metabolic cost and dynamic stability in 15 recreational runners who experienced sudden slip-like anteroposterior perturbations (SLAPs) during treadmill running (2.5 m/s). Following SLAPs, a significant 3.4% increase in the cost of transport was observed. However, there were no significant changes in single gait parameters or lower limb kinematics in the sagittal plane. Future investigations should explore the underlying neuromuscular mechanisms and broader functional biomechanical variables. Overall, we show that human motor control prioritizes dynamic stability more when expecting SLAPs compared to non-expecting them, highlighting a potential trade-off between metabolic efficiency and traumatic injury prevention that warrants further exploration of underlying mechanisms
AUTOMATED ROWER ASSIGNMENT TO ROWING EVENTS: A MACHINE LEARNING APPROACH
Get PDFThe purpose was to assign rowers to different rowing events based on their demographics and rowing kinematics using machine learning models. 55 elite athletes were instructed to row on a rowing ergometer for one minute at three stroke rates. Trunk, pelvis, and shoulder 3D kinematics were collected using an IMU system at a sampling rate of 100 Hz. Trunk and upper arm segmental and joint range of motion were generated. Trunk segments and upper arm motion coordination were analysed using the vector coding method. Six supervised machine learning models were trained using demographic and kinematic features to classify rowers’ groups. The machine learning models successfully classified rowers’ groups (accuracy up to 0.94). The rowing event assignment automated by machine learning may help coaches make more informed and objective decisions
THE CORRELATION BETWEEN LUMBOPELVIC CONTROL AND PITCHING VELOCITY IN BASEBALL PITCHERS
Get PDFThe purpose of this study was to investigate the relationship between lumbopelvic control and pitching performance among baseball pitchers. Four baseball pitchers participated in this pilot study. Each participant underwent measurements for lumbopelvic control ability in static posture and dynamic movement, as well as pitching performance assessments. The results indicated a significant correlation between lumbopelvic control in the static posture of the stride leg and pitching velocity (Rs = -1.0, p \u3c 0.01), as well as a significant correlation between lumbopelvic control in dynamic movement and pitching velocity (Rs = - 0.90, p = 0.04). Therefore, lumbopelvic control during pitching could play a pivotal role in enhancing pitching velocity. Coaches and practitioners should prioritize strategies aimed at improving these aspects to potentially enhance pitching velocity
APPLYING DOSE-RESPONSE ANALYSIS IN SPORT BIOMECHANICS: AN EXAMPLE OF BADMINTON FOOTWORK AND FOOTWEAR
Get PDFEfficient footwork and appropriate footwear are important elements in badminton. This study aims to report the application of dose-response analysis in sports biomechanics, presenting the example of analysing the biomechanical response to training intervention with increased wearable resistance (WR) loads and the response of footwork performance to systematically increased wedge hardness in the design of badminton footwear. A further technique of data dimensionality reduction was employed to decipher the dose-response effect via reporting key PC explanation of ~90% with WR intervention, and 61.98%, 21.26%, and 8.1%. The example of badminton biomechanics may provide implications for future research and data analysis, especially understanding dose effect and biomechanical response in sports biomechanics
GENDER DIFFERENCES IN INTER-SEGMENT FOOT KINETICS DURING RUNNING
Get PDFGender differences in kinetics may be associated with the incidence of specific overuse injuries. However, inter-segment foot kinetics during running have not been investigated between genders. The purpose of this study was to compare multi-segment foot kinetics during running between males and females. Eleven males and nine females ran barefoot with rearfoot strike at 3.3 m/s ± 10% along a 10 m runway. Segmental moment and power at midfoot and ankle in sagittal plane were calculated, and peak moment, positive and negative power were compared by gender. Peak positive and negative midfoot power were significantly larger in females than in males. These results suggest the soft tissues across midfoot contract more concentrically or eccentrically in females. The contribution of midfoot to shock absorption and forward propulsion seems to be different according to gender
SOFTBALL PLAYERS WITH SHOULDER INJURIES EXHIBIT UPPER-BODY COMPENSATORY STRATEGIES COMPARED TO HEALTHY CONTROLS: A WEARABLE INERTIAL SENSORS STUDY
Get PDFThe aim of the study was to assess the kinematic differences in the upper limb and trunk between healthy and shoulder-injured softball players. Eleven first-division softball players (mean age 25.9±8.1) were enrolled. Five players experienced a shoulder injury with consequent surgery. The players were assessed while performing a standard throw, from the moment when they pick up a ball on the ground (Pick-up Phase) to the complete throw (Pass Phase), using 11 wearable inertial sensors (Xsens MTw Awinda). Peak joint kinematics and range of motion (ROM) were analysed. The shoulder-injured players showed less shoulder internal/external rotation (
Comparing the Predictive Capacity of Allometric Models in Estimating Grass Biomass in a Desert Grassland
Get PDFAllometric models provide a rapid, nondestructive means for estimating aboveground biomass (AGB) of perennial grass species. In the absence of site-specific models, allometric relationships developed at other sites at other times are often used. This implicitly assumes that size-biomass relationships are highly robust. In this study, we assess the comparability of allometric relationships developed at two points in time (2005 and 2015) on different soils on a Sonoran Desert savanna in southern Arizona. We used peak growing season field measurements to develop single-species and multispecies regression models using basal diameter and height to predict the current year\u27s AGB for seven perennial grass species. Basal diameter exhibited the strongest relationship with AGB among single-species (adjusted R2 = 0.54 to 0.87) and multispecies models (adjusted R2 = 0.73). Inclusion of height did little to improve biomass predictions. Our models generally underestimated observed 2015 AGB on the loamy site, whereas models developed in 2005 on a sandier site overestimated the 2015 AGB. Results suggest site-specific allometric models should be used when possible. However, in lieu of such models, relationships developed at other sites or at other times may be appropriate depending on the level of precision needed to address a specific research question
Climate Change and American Higher Education: Inculcating the Self-Deception of Capitalist Society
Get PDFEFFECTS OF VISION AND MULTIPLE COGNITIVE TASKS ON PRE-LANDING AND EARLY LANDING MECHANICS ASSOCIATED WITH ACL LOADING
Get PDFThe aim of the study was to assess the effect of vision and 1 or 2 cognitive tasks on lower extremity biomechanics associated with ACL loading variables (knee flexion angles, increased impact forces, and knee extension moments) during single-leg drop landing tasks. Thirty-four participants performed landing tasks with or without vision and with or without 1-2 cognitive tasks. The cognitive tasks included counting backward and/or recalling the number of beeping tones. The results indicated counting backward significantly decreased knee angles, and a lack of vision could increase impact forces. However, the combination of two cognitive tasks did not result in the greatest ACL loading variables. Further research is needed to better understand the implications of cognitive distractions on ACL injury risk during more complex athletic movements
LANDING KINEMATICS AND MUSCLE ACTIVITY IN RUN-ON AND TWO-FOOT LANDINGS BETWEEN ATTACKING AND DEFENSIVE NETBALL PLAYERS
Get PDFThe purpose of this study was to investigate landing kinematics and muscle activity differences in run-on and two-foot landings between attacking and defensive netball players. Eight British Universities and Colleges Sport (BUCS) level female players performed eight run-on and eight two-foot landing trials. In comparison to two-foot landings, run-on landings promote a smaller peak flexion at the hip and ankle, smaller range of motion at the hip and knee, and a more acute touchdown angle at the hip and knee. Furthermore, attacking players displayed a less flexed knee angle at touchdown compare to defensive players. This suggests run-on landings promote a stiffer, more upright landing mechanism resulting in increased anterior cruciate ligament (ACL) loading, with attacking players exhibiting a more ACL-damaging landing mechanism