Quantification in shooting precision for preferred and non-preferred foot in college soccer players using the 95% equal confidence ellipse.

Shooting precision is a fundamental characteristic in soccer, yet the probabilistic structure and magnitude of precision in soccer shooting remain quantitatively unexplored. This study aimed to quantify shooting precision using measures derived from the bivariate normal distribution for both preferred and non-preferred feet. Sixteen right-footed collegiate soccer players participated by performing instep kicks aiming at targets which are placed close to the left and right top corners of the soccer goal.

Off-camera gaze decreases evaluation scores in a simulated online job interview.

During the pandemic, digital communication became paramount. Due to the discrepancy between the placement of the camera and the screen in typical smartphones, tablets and laptops, mutual eye contact cannot be made in standard video communication. Although the positive effect of eye contact in traditional communication has been well-documented, its role in virtual contexts remains less explored.

Guidelines for balancing the number of trials and the number of subjects to ensure the statistical power to detect variability - Implication for gait studies.

Variability is one of the most crucial outcomes in human movement studies: variance and standard deviation of various parameters have been reported in numerous studies. However, in many of these studies, the numbers of trials and subjects have been intuitively determined and not justified with statistical considerations. Here, we investigated the impact of the numbers of trials and subjects on statistical power, based on the assumption that results per trial follow a normal distribution, using mathematical analysis and numerical simulation.

Comparison of sensitivity among dynamic balance measures during walking with different tasks.

Although various measures have been proposed to evaluate dynamic balance during walking, it is currently unclear which measures are most sensitive to dynamic balance. We aimed to investigate which dynamic balance measure is most sensitive to detecting differences in dynamic balance during walking across various gait parameters, including short- and long-term Lyapunov exponents ( and ), margin of stability (MOS), distance between the desired and measured centre of pressure (dCOP-mCOP) and whole-body angular momentum (WBAM). A total of 10 healthy young adults were asked to walk on a treadmill under three different conditions (normal walking, dual-task walking with a Stroop task as an unstable walking condition, and arm-restricted walking with arms restricted in front of the chest as another unstable walking condition) that were expected to have different dynamic balance properties.

Shape of an obstacle affects the mediolateral trajectory of the lower limb during the crossing process.

In previous studies involving obstacle crossing, vertical foot clearance has been used as an indicator of the risk of contact. Under normal circumstances, individuals do not always cross over obstacles with the same height on both sides, and depending on the shape of the obstacle, the risk of contact may differ depending on the foot elevation position. Therefore, we investigated whether task-related control of the mediolateral foot position is adapted to the shape of the obstacle.

Dynamic stability during level walking and obstacle crossing in children aged 2-5 years estimated by marker-less motion capture.

In the present study, dynamic stability during level walking and obstacle crossing in typically developing children aged 2-5 years ( = 13) and healthy young adults ( = 19) was investigated. The participants were asked to walk along unobstructed and obstructed walkways. The height of the obstacle was set at 10% of the leg length.

Use of the Azure Kinect to measure foot clearance during obstacle crossing: A validation study.

Obstacle crossing is typical adaptive locomotion known to be related to the risk of falls. Previous conventional studies have used elaborate and costly optical motion capture systems, which not only represent a considerable expense but also require participants to visit a laboratory. To overcome these shortcomings, we aimed to develop a practical and inexpensive solution for measuring obstacle-crossing behavior by using the Microsoft Azure Kinect, one of the most promising markerless motion capture systems.

A biomechanics analysis of the judo osoto-gari technique: comparison of black belt and white belt judokas.

The purpose of this study was to determine biomechanical factors for the effective execution of the osoto-gari technique by comparing differences between black belt and white belt judokas. Twenty-two male judokas (12 black belts; 10 white belts) performed osoto-gari, and the motion data were recorded using a Mac3D motion analysis system (250 Hz). The peak angular momentums of the trunk and leg of the uke were larger in the black belts than in the white belts, suggesting that the black belts rotated the uke's body more effectively than the white belts.

Variability in the Center of Mass State During Initiation of Accurate Forward Step Aimed at Targets of Different Sizes.

Motor control for forward step initiation begins with anticipatory postural adjustments (APAs). During APAs, the central nervous system controls the center of pressure (CoP) to generate an appropriate center of mass (CoM) position and velocity for various task requirements. In this study, we investigated the effect of required stepping accuracy on the CoM and CoP parameters during APA for a step initiation task.

Foot clearance when crossing obstacles of different heights with the lead and trail limbs.

Background: In order to predict and prevent falls and fall-related injuries, it is crucial to understand the motor control for crossing obstacles. In real life, since obstacles do not always take regular shapes like rectangles, the lead and trail limbs sometimes need to negotiate different obstacle heights. The interlimb interaction in this process has remained unknown, since obstacle crossing studies commonly use a single-obstacle paradigm in which the obstacle height is the same for the lead and trail limbs.

Larger, but not better, motor adaptation ability inherent in medicated Parkinson's disease patients revealed by a smart-device-based study.

Generating appropriate motor commands is an essential brain function. To achieve proper motor control in diverse situations, predicting future states of the environment and body and modifying the prediction are indispensable. The internal model is a promising hypothesis about brain function for generating and modifying the prediction.

Human Navigational Strategy for Intercepting an Erratically Moving Target in Chase and Escape Interactions.

Pursuit and interception of moving targets are fundamental skills of many animal species. Although previous studies in human interception behaviors have proposed several navigational strategies for intercepting a moving target, it is still unknown which navigational strategy humans use in chase-and-escape interactions. In the present experimental study, by using two one-on-one tasks as seen in ball sports, we showed that human interception behaviors were statistically consistent with a time-optimal model.

Spatiotemporal characteristics of an attacker's strategy to pass a defender effectively in a computer-based one-on-one task.

For modern humans, chase-and-escape behaviors are fundamental skills in many sports. A critical factor related to the success or failure of chase-and-escape is the visuomotor delay. Recent studies on sensorimotor decision making have shown that humans can incorporate their own visuomotor delay into their decisions.

Underlying structure in the dynamics of chase and escape interactions.

Chase and escape behaviors are important skills in many sports. Previous studies have described the behaviors of the attacker (escaper) and defender (chaser) by focusing on their positional relationship and have presented several key parameters that affect the outcome (successful attack or defense). However, it remains unclear how each individual agent moves, and how the outcome is determined in this type of interaction.

Sub-optimality in motor planning is not improved by explicit observation of motor uncertainty.

To make optimal decisions under risk, one must correctly weight potential rewards and penalties by the probabilities of receiving them. In motor decision tasks, the uncertainty in outcome is a consequence of motor uncertainty. When participants perform suboptimally as they often do in such tasks, it could be because they have insufficient information about their motor uncertainty: with more information, their performance could converge to optimal as they learn their own motor uncertainty.

Transcranial Direct Current Stimulation Over Dorsolateral Prefrontal Cortex Modulates Risk-Attitude in Motor Decision-Making.

Humans often face situations requiring a decision about where to throw an object or when to respond to a stimulus under risk. Several behavioral studies have shown that such motor decisions can be suboptimal, which results from a cognitive bias toward risk-seeking behavior. However, brain regions involved in risk-attitude of motor decision-making remain unclear.

Risk aversion in the adjustment of speed-accuracy tradeoff depending on time constraints.

Humans are often required to make decisions under time constraints and to adjust speed-accuracy tradeoff (SAT) based on time constraints. Previous studies have investigated how humans adjust SAT depending on the time discount rate of expected gain. Although the expected gain of actions can be determined by both gain and probability, only situations where gain decreases over time have been tested.

Accent Stabilizes 1:2 Sensorimotor Synchronization of Rhythmic Knee Flexion-Extension Movement in Upright Stance.

Numerous studies have shown the importance of metrical structure on beat perception and sensorimotor synchronization (SMS), which indicates why metrical structure has evolved as a widespread musical element. In the current study, we aimed to investigate the effect of metrical structure with or without accented sounds and the alignment of accent with flexion or extension movements on the stability of 1:2 SMS in rhythmic knee flexion-extension movement in upright stance (flexing the knee once every two sounds). Fourteen participants completed 1:2 rhythmic knee flexion-extension movements with a metronome beat that accelerated from 2 to 8 Hz (the frequency of the movement was 1-4 Hz).

Asymmetric Adaptability to Temporal Constraints Among Coordination Patterns Differentiated at Early Stages of Learning in Juggling.

In this study, we examined the degree of adaptability to new constraints after learning of a fundamental skill in juggling. Adaptation of sensorimotor synchronization with the various constraints is important for expertise. However, this adaptability may not be equivalent between coordination patterns which learners acquired in the previous learning process.

Cognitive Bias for the Distribution of Ball Landing Positions in Amateur Tennis Players (Cognitive Bias for the Motor Variance in Tennis).

This study aimed to investigate whether the isotropy bias (estimating one's own motor variance as an approximately circular distribution rather than a vertically elongated distribution) arises in tennis players for the estimation of the two-dimensional variance for forehand strokes in tennis (Experiment 1), as well as the process underlying the isotropy bias (Experiment 2). In Experiment 1, 31 tennis players were asked to estimate prospectively their distribution of ball landing positions. They were then instructed to hit 50 forehand strokes.

Baseball pitching accuracy: an examination of various parameters when evaluating pitch locations.

This study evaluated baseball pitching accuracy using a variety of parameters to quantify pitching errors and analysed the validity of the accuracy measurements by comparing the outcomes of two small groups of pitchers. Several professional (n = 5) and high school (n = 8) pitchers threw 30 pitches each, including 20 fastballs and 10 breaking balls. To assess pitching accuracy, pitch locations relative to the catcher's mitt (as the target) were evaluated with various parameters, including major/minor radius, an area of 95% confidence ellipse, absolute error, constant error and pitch location trajectory.