Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.humov.2021.102908

Language：English   Publishing type：Research paper (scientific journal)  

Purpose: This study examined the effect of manipulating advanced kinematic information about opponents' pitching movement on ball speed prediction, ball speed perception, and impact timing errors under strict temporal constraints (i.e., a softball game). Method: Three experiments were conducted using visual stimuli consisting of varied kinematic information-different pitching movements with the same ball trajectory. In Experiment 1, participants observed the pitching movement of the visual stimuli and predicted pitched ball speed as a two-interval forced choice discrimination task (2IFC). In Experiment 2, participants observed both the pitching movement and ball trajectory, and evaluated the pitched ball speed as a 2IFC. In Experiments 3a and 3b, they tried to swing against the pitched ball presented on the screen as accurately as possible with regard to timing. Results: Batters tended to predict the ball was moving faster when the pitching movement was faster (Experiment 1). Incorrectly predicting the ball speed due to the difference in advanced kinematic information also biased batters' perception of the speed (Experiment 2), and this biased prediction yielded congruent impact timing (Experiment 3a). The impact timing error of naive participants also was affected by kinematic information (Experiment 3b). Conclusion: Limitations of this study (representative task design, sample size, and experimental procedures) notwithstanding, results indicate that, under strict temporal constraints, batters' perceptions and actions are sensitive to advanced kinematic information, which could lead to biased perceptions and actions.

DOI： 10.1080/02701367.2020.1773375

Web of Science

PubMed

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1080/17461391.2021.1905077

Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：JOURNAL SPORTS SCIENCE & MEDICINE  

Interpersonal coordination is an important skill for promoting collective behavior in team sports. This study tested the impact of two types of tools in facilitating triadic coordination. 16 males aged under 12 years were divided into four groups with similar skill levels and average ages. Each group performed a three-versus-one ball passing task under three conditions: a one-elasticband tool linking the three players, a three-elastic-bands tool linking the three players, and without a tool linking the three players. The dependent variables were ball passing frequency, frequency and amplitude of inner angles of the triangle formed by the players, and duration of the synchronized patterns of the inner angles. The results show that neither tool increased ball-passing frequency or the duration of synchronized patterns. However, both tools increased the frequency of inner angles, and the three-elastic-bands tool decreased the amplitude of inner angles. From these results, we conclude that elastic-band tools affect spatial and temporal triadic formation by means of haptic and visual information. Specifically, compared with the one-elastic-band tool, the three-elastic-bands tool stabilizes the triadic spatial formation. We also explore the implications for how these tools can be used in practice.

Web of Science

Authorship：Lead author   Language：Japanese   Publishing type：Research paper (scientific journal)  

Language：Japanese   Publishing type：Research paper (other academic)  

Language：English   Publishing type：Research paper (scientific journal)  

This study aims to clarify the relationship between task constraints and the preparatory movement of fast-pitch softball batters in Japan for three different competition categories, namely high school, college, and league. As task constraints, we focused on the temporal and tool constraints and evaluated preparatory movements using initiation time and step duration of the stepping movement in a striking action. First, we confirmed the temporal constraints in each category and then examined the relationship between the temporal constraints and the stepping movements. The results demonstrated that the temporal constraints affected both initiation time and step duration of the stepping movements. Hierarchical cluster analysis was applied to the two variables. Consequently, the stepping movement of the softball players was classified into three types: “late initiation–short duration” (LS), “early initiation–short duration” (ES), and “early initiation–long duration” (EL) corresponding to the task constraints. Finally, the relationship between the task constraints of each category and the stepping movements was examined. The results revealed that high school players exhibited mostly the LS- or EL-type stepping movement; college players exhibited mostly the EL-type stepping movement; and league players exhibited all types. These results depict that the players in each category with each temporal and tool constraint exhibited particular types of stepping movements as a preparatory movement corresponding to each task constraint, thereby arguing that players use a not-to-lose strategy exploiting the redundancy in solutions under various task constraints.

DOI： 10.1371/journal.pone.0212997

Web of Science

Scopus

PubMed

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.3390/app9010039

Web of Science

Language：Japanese   Publishing type：Research paper (scientific journal)  

We explored how practice and actual putting strokes differed between professionals and high-level golf amateurs, and how practice strokes reflected subtle differences in putting distances. We analysed swing amplitude, impact velocity, and acceleration profile of the club-head. The acceleration profiles showed that the motor control pattern of the practice stroke differed from that of the actual stroke. To clarify the effects of different putting distances on the practice stroke and to analyse how much the actual stroke could be explained by the practice stroke, we conducted individual regression analyses. The practice strokes of all participants could be divided into three strategies and five types by the coefficient of determination and the slope. This implies that the purpose of the practice stroke varied among golfers. Most golfers used the individual velocity criteria in their practice strokes, which resulted in different putting distances based on their criteria. Unexpectedly, we found no significant difference in skill level between professionals and high-level amateurs. The results of this study imply that the practice stroke does not duplicate the actual stroke, even for professional golfers with excellent skills. However, most high-level golfers adopted distance-dependent control strategies for slightly different putting distances.

DOI： 10.1080/17461391.2019.1595159

Web of Science

PubMed

Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：American Physical Society  

Team coordination is a basic human behavioral trait observed in many real-life communities. To promote teamwork, it is important to cultivate social skills that elicit team coordination. In the present work, we consider which social skills are indispensable for individuals performing a ball possession game in soccer. We develop a simple social force model that describes the synchronized motion of offensive players. Comparing the simulation results with experimental observations, we uncovered that the cooperative social force, a measure of perception skill, has the most important role in reproducing the harmonized collective motion of experienced players in the task. We further developed an experimental tool that facilitates real players' perceptions of interpersonal distance, revealing that the tool improves novice players' motions as if the cooperative social force were imposed.

DOI： 10.1103/PhysRevE.97.022410

Web of Science

Scopus

Language：Japanese   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1038/srep23911

Authorship：Lead author   Language：Japanese  

Language：English   Publishing type：Research paper (scientific journal)  

Language：English  

Language：Japanese   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：English  

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：Japanese   Publishing type：Research paper (bulletin of university, research institution)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：Japanese   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：Japanese  

Language：English   Publishing type：Research paper (scientific journal)  

Language：Japanese   Publishing type：Research paper (bulletin of university, research institution)  

Language：Japanese   Publishing type：Research paper (scientific journal)  

Language：English  

Language：English   Publishing type：Research paper (bulletin of university, research institution)  

Language：Japanese   Publishing type：Research paper (bulletin of university, research institution)  

Language：Japanese  

We developed a new method to clarify the local characteristics of football games using a dominant landscape. The idea is founded on a Voronoi diagram; however, it is calculated using distance between generators. The new method is based on the temporal aspect, and the calculated minimum arrival times to all regions of the football field divided by a square meter for each player. We considered the velocity of the players in each frame by referring to previous research. Then, we calculated the dominant values, which showed how long it would take for each of the six players on the two teams to reach the ball position in every frame. In a successful offensive play, the dominant value of the offensive team was larger than that of the defensive team. This finding implies that momentum, that is, the velocities of offensive players, could be evaluated using this new method.

DOI： 10.18999/njhpfs.41.1.5

CiNii Books

Other Link： http://hdl.handle.net/2237/00028365

Language：Japanese  

The purpose of this study was to examine how individual decision-making is affected by the waiting and hitting positions during singles tennis. The ideal waiting position for the receiver was defined by the hitting position of the opponent, which depended on the depth and width of the hitter's position. The definition was applied to three international men's singles matches, and the constant errors between ideal and actual waiting positions and between ideal waiting positions and the direction of the shots in each rally were determined, as receivers' and hitters' decisionmaking, respectively. The results showed that the number of rallies on the advantage side was more than that on the deuce side, and more crosscourt shots occurred from the advantage side than down-the-line shots; however, shots from the deuce side were directed to both sides. The distribution of the waiting positions for receivers was unimodal; however, the directions of the shots showed a bimodal distribution. These results suggest that the receiver makes a decision depending on the perception of the hitting position of the hitter, and the hitter makes a decision depending on the perception of the receiver's waiting position.

DOI： 10.18999/njhpfs.40.1.45

CiNii Books

Other Link： http://hdl.handle.net/2237/26901

Language：Japanese  

The purpose of this study was to identify the characteristics of impact sounds in tennis service and to clarify the common and unique characteristics among 8 top-level tennis players. The sound data was obtained from the matches in The Championships, Wimbledon 2016, and the waveforms of impact sounds in service for 8 male top-level players were collected. The results showed that impact sounds in service had common characteristics of waveforms, which were eight peaks, three clusters in the eight peaks, and the same inter-peaks intervals between both court sides among 8 players, regardless of speed of service, ball direction or other factors which may affect the audio components. Also each player showed his own unique characteristics on the amplitude and duration of the impact sounds.

DOI： 10.18999/njhpfs.40.1.37

CiNii Books

Other Link： http://hdl.handle.net/2237/26900

Language：Japanese  

This study considered the movements of the defense lines and the ball during a football game as a three-coupled oscillation. Each defense line of two opposing teams oscillated with in-phase synchronization, and the length between each defense line and the ball oscillated with anti-phase synchronization. We introduced a three-coupled oscillation model to understand these synchronizations. First, we considered the case in which three masses, m, and four spring constants, k, were equal in a three-coupled oscillation. We calculated the eigenvectors and eigenvalues based on the equation of motion, and we obtained three modes of oscillation as three angular frequencies in the equation. We obtained key parameters when we defined the initial state of the system, which allowed us to solve the equation of motion for three-coupled oscillation. Next, we considered cases in which three masses and four spring constants differed. To confirm the validity of the three-coupled oscillation model, we calculated the distribution of the relative phase between two outer masses, m1 and m3, as defense lines and the length between two outer masses and the middle mass, m2, as each defense line and the ball. The three-coupled oscillations showed similar distributions of the relative phase. However, the periodogram showed distinct periodicity. Thus, a more sophisticated model is needed to understand the behavior of the defense lines and the ball during football games.

DOI： 10.18999/njhpfs.40.1.1

CiNii Books

Other Link： http://hdl.handle.net/2237/26896

Event date： 2022.11

Presentation type：Public lecture, seminar, tutorial, course, or other speech  

Event date： 2021.8

Language：Japanese   Presentation type：Public lecture, seminar, tutorial, course, or other speech  

Venue：オンライン   Country：Japan  

Event date： 2018.8

Language：English   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2018.7

Language：English   Presentation type：Oral presentation (general)  

Venue：Lisbon, Portugal   Country：Japan  

Event date： 2017.11

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：名古屋大学   Country：Japan  

Event date： 2017.7

Language：English   Presentation type：Poster presentation  

Venue：University of Sevilla, Spain   Country：Spain  

Event date： 2016.11

Language：Japanese   Presentation type：Poster presentation  

Country：Japan  

Event date： 2016.9

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2016.9

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2016.8

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2016.8

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2016.3

Language：English   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2015.8

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2015.7

Language：English   Presentation type：Oral presentation (general)  

Country：United States  

Event date： 2014.12

Language：English   Presentation type：Poster presentation  

Country：Japan  

Event date： 2014.8

Language：Japanese   Presentation type：Symposium, workshop panel (nominated)  

Country：Japan  

Event date： 2013.11

Language：English   Presentation type：Poster presentation  

Country：United States  

Event date： 2013.9

Language：English   Presentation type：Symposium, workshop panel (public)  

Country：Japan  

Event date： 2012.10

Language：English   Presentation type：Poster presentation  

Country：United States  

Event date： 2012.9

Language：English   Presentation type：Poster presentation  

Country：Japan  

Event date： 2012.9

Language：Japanese   Presentation type：Symposium, workshop panel (nominated)  

Country：Japan  

Event date： 2012.8

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2012.7

Language：English   Presentation type：Poster presentation  

Country：Spain  

Event date： 2012.7

Language：English   Presentation type：Poster presentation  

Country：Germany  

Event date： 2011.10

Language：Japanese   Presentation type：Symposium, workshop panel (nominated)  

Country：Japan  

Event date： 2011.8

Language：English   Presentation type：Poster presentation  

Country：United States  

Event date： 2010.9

Language：English   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2009.11

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2009.1

Language：English   Presentation type：Poster presentation  

Country：Australia  

Event date： 2008.11

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2008.9

Language：Japanese   Presentation type：Poster presentation  

Country：Japan  

Event date： 2007.9

Language：English   Presentation type：Poster presentation  

Country：Japan  

Event date： 2007.9

Language：Japanese   Presentation type：Poster presentation  

Country：Japan  

Event date： 2007.9

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2006.8

Language：English   Presentation type：Poster presentation  

Country：Japan  

Event date： 2006.8

Language：English   Presentation type：Oral presentation (general)  

Country：Japan  

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：名古屋大学