. To develop analytical formulas which can serve as quantitative guidelines for the selection of the sampling rate for the electrocardiogram (ECG) required to calculate heart rate (HR) and heart rate variability (HRV) with a desired level of accuracy..
View Article and Find Full Text PDFDevelopmental Coordination Disorder (DCD), also known as Dyspraxia, is characterized by movement difficulties in individuals without discernible neurological disorders or identifiable medical conditions. Previous studies from various countries have highlighted disparities in anthropometric, physical activity, and psychological characteristics between children diagnosed with DCD and their typically developing (TD) peers. These differences are influenced by sociocultural norms and geographical locations.
View Article and Find Full Text PDFHigh-velocity actions are central to clinical and athletic performance, with jumping used to assess outcomes in sports medicine. Ground reaction force (GRF)-based methods are the standard for computing jump characteristics, but require mass estimation and GRF integration, potentially resulting in mass errors which influence outcomes. This study investigated how simulated mass errors influenced the centre of mass (CoM) trajectory during a countermovement jump.
View Article and Find Full Text PDFAthletic shoes that induce dorsiflexion in standing can improve jump height compared to traditional athletic shoes that induce plantarflexion, but it is unknown if dorsiflexion shoes (DF) also affect landing biomechanics associated with lower extremity injury risk. Thus, the purpose of this study was to investigate if DF adversely affect landing mechanics related to patellofemoral pain and anterior cruciate ligament injury risk compared to neutral (NT) and plantarflexion (PF) shoes. Sixteen females (21.
View Article and Find Full Text PDFBackground: The knee adduction moment, a biomechanical risk factor of knee osteoarthritis, is typically measured in a gait laboratory with expensive equipment and inverse dynamics modeling software. We aimed to develop a framework for a portable knee adduction moment estimation for healthy female individuals using deep learning neural networks and custom instrumented insole and evaluated its accuracy compared to the standard inverse dynamics approach.
Methods: Feed-forward, convolutional, and recurrent neural networks were applied to the data extracted from five piezo-resistive force sensors attached to the insole of a shoe.
We investigated the role of task constraints on interpersonal interactions. Twenty-one pairs of coworkers performed a finger force production task on force sensors placed at two ends of a seesaw-like apparatus and matched a combined target force of 20 N for 23 s over 10 trials. There were two experimental conditions: ) FIXED: the seesaw apparatus was mechanically held in place so that the only task constraint was to match the 20 N resultant force, and ) MOVING: the lever in the apparatus was allowed to rotate freely around its fulcrum, acting like a seesaw, so an additional task constraint to (implicitly) balance the resultant moment was added.
View Article and Find Full Text PDFContext: Understanding if roller massage prior to a run can mitigate fatigue-related decrements in muscle force production during prolonged running is important because of the association between fatigue and running-related injury.
Objective: The authors investigated whether a bout of roller massage prior to running would (1) mitigate fatigue-related increases in vertical average load rate and free moment of the ground reaction force of running and (2) mitigate decreases in maximal countermovement jump height.
Design: Repeated-measures study.
The purpose of this study was to investigate how the ball position along the mediolateral (M-L) direction of a golfer causes a chain effect in the ground reaction force, body segment and joint angles, and whole-body centre of mass during the golf swing. Twenty professional golfers were asked to complete five straight shots for each 5 different ball positions along M-L: 4.27 cm (ball diameter), 2.
View Article and Find Full Text PDFObjective: Energy-storage-and-return (ESAR) prosthetic feet have improved amputee mobility due to their efficient conversion of strain energy to mechanical work. However, this efficiency is typically achieved using light-weight, high-stiffness materials, which generate high-frequency vibrations that are potentially injurious if transmitted to biological tissues. To reduce the vibration which may cause cumulative tissue trauma, high-frequency vibration suppression by piezoelectric shunt damping patches on a commercial ESAR foot was evaluated.
View Article and Find Full Text PDFProfessional dancers demonstrate an amazing ability to control their balance. However, little is known about how they coordinate their body segments for such superior control. In this study, we investigated how dancers coordinate body segments when a physical perturbation is given to their body.
View Article and Find Full Text PDFFront Hum Neurosci
October 2020
Evidence from recent studies on animals and humans suggest that neural overflow from the primary sensory cortex (S1) to the primary motor cortex (M1) may play a critical role in motor control. However, it is unclear if whole-body maximal motor tasks are also governed by this mechanism. Maximum vertical squat jumps were performed by 15 young adults before cooling, then immediately following a 15-min cooling period using an ice-water bath for the foot soles, and finally immediately following a 15-min period of natural recovery from cooling.
View Article and Find Full Text PDFStudies of running mechanics often use a standardized lab shoe, ostensibly to reduce variance between subjects; however, this may induce unnatural running mechanics. The purpose of this study was to compare the step rate, vertical average loading rate, and ground contact time when running in standardized lab shoes versus participants' normal running shoes. Ground reaction forces were measured while the participants ran overground in both shoe conditions at a self-selected speed.
View Article and Find Full Text PDFThe interventional cardiology is growing and evolving. Many complex procedures are now performed outside the operating room to manage cardiovascular pathologies which had been traditionally treated with cardiac surgery. Appropriate sedation strategy is crucial for improved patient comfort and successful procedure while ensuring safety.
View Article and Find Full Text PDFIn human movement control, inherent error or uncertainty in the controller, motor system, and sensory system causes variability in motor outcomes. Previous studies have suggested different methods to quantify and examine independent components of the motor variability of motor outputs in a redundant motor system. While these motor variability components are mathematically independent, it is unknown if these components are behaviorally independent among subjects.
View Article and Find Full Text PDFMed Sci Sports Exerc
June 2019
Purpose: As running speed increases there are concomitant changes in loads associated with tibial stress fracture risk. Runners often include multiple speeds in their training, but the effect of speed distribution on load accumulation is unknown. We studied how running at different proportions of speed within a given running distance affects the cumulative loading of the vertical average loading rate, cumulative peak absolute tibial free moment, and cumulative peak axial tibial load.
View Article and Find Full Text PDFWhen a person plays a musical instrument, sound is produced and the integrated frequency and intensity produced are perceived aurally. The central nervous system (CNS) receives defective afferent signals from auditory systems and delivers imperfect efferent signals to the motor system due to the noise in both systems. However, it is still little known about auditory-motor interactions for successful performance.
View Article and Find Full Text PDFObjective: The objective of this study was to investigate three-dimensional lower extremity joint moment differences between limbs and speed influences on these differences in individuals with lower extremity amputations using running-specific prostheses.
Design: Eight individuals with unilateral transtibial amputations and 8 control subjects with no amputations ran overground at three constant velocities (2.5, 3.
The hand, one of the most versatile but mechanically redundant parts of the human body, suffers more and longer than other body parts after stroke. One of the rehabilitation paradigms, task-oriented rehabilitation, encourages motor repeatability, the ability to produce similar motor performance over repetitions through compensatory strategies while taking advantage of the motor system's redundancy. The previous studies showed that stroke survivors inconsistently performed a given motor task with limited motor solutions.
View Article and Find Full Text PDFChu, E, Kim, Y-S, Hill, G, Kim, YH, Kim, CK, and Shim, JK. Wrist resistance training improves motor control and strength. J Strength Cond Res 32(4): 962-969, 2018-The aim of this study was to investigate the effects of a 6-week direction-specific resistance training program on isometric torque control and isokinetic torque strength of the wrist joint.
View Article and Find Full Text PDFCompared to intact limbs, running-specific prostheses have high resonance non-biologic materials and lack active tissues to damp high frequencies. These differences may lead to ground reaction forces (GRFs) with high frequency content. If so, ubiquitously applying low-pass filters to prosthetic and intact limb GRFs may attenuate veridical high frequency content and mask important and ecologically valid data from prostheses.
View Article and Find Full Text PDFAim: The purpose of the present study was to evaluate the efficacy of two different exercise types, rhythmic exercise designed from local music and dance (RE) and walking exercise (WE), in terms of exercise participation and physical function changes in older adults over a period of 12 weeks.
Methods: Exercise participation was assessed through the attendance rate and retention rate, and physical function was evaluated through the Short Physical Performance Battery, static balance test and gait test.
Results: The RE group showed significantly higher attendance and retention rates; greater improvement in Short Physical Performance Battery scores; and greater improvement in static balance, as compared with the WE.
Multicellular spheroids are obtained in a variety of three-dimensional (3D) culture systems without the use of supporting scaffold. We present here a 3D culture method that resulted in a multicellular sheet under scaffold-free conditions. A floating disk-shaped 3D culture was prepared by magnetic levitation of B16F10 cells that has ingested FeO-containing fibroin microspheres.
View Article and Find Full Text PDFHumans detect changes in the air pressure and understand the surroundings through the auditory system. The sound humans perceive is composed of two distinct physical properties, frequency and intensity. However, our knowledge is limited how the brain perceives and combines these two properties simultaneously (i.
View Article and Find Full Text PDFBackground: Adolescent idiopathic scoliosis is a prevalent orthopedic problem in children ages 10 to 16years. Although genetic, physiological and biomechanical factors are considered to contribute to the onset and progression of adolescent idiopathic scoliosis, the underlying mechanisms are not yet clear. The purpose of this study was to investigate the association between spinal deformity and inter-leg ground reaction force asymmetry during walking in adolescent idiopathic scoliosis patients.
View Article and Find Full Text PDF