Hitoshi Yanagi

Toward curling informatics — Digital scorebook development and game information analysis

This paper introduces the concept of curling informatics and the digital scorebook system iCE which was developed to support strategies and tactics in curling - a winter team sport played on ice. Our project aims to develop an environment to support curling strategies and tactics by realizing methods to record game information, analyzing, visualizing and sharing the information. We developed the digital scorebook system iCE (intelligent Curling Elicitator) as the first step of our concept. We tested our system by recording real game information at the top-level championships. Consequently, we confirmed that the system performs adequately for practical use. Moreover, we analyzed the recorded information in detail, and the results suggest differences in shot accuracies relating to the differences in game scores. This suggests that our proposed method can effectively support strategic/tactical planning in curling games.

Dynamic and Static Ability of Balance and Postural Control in Japanese Obese Children

The purpose of this study was to examine dynamic and static ability of balance and postural control in obese female children and healthy male adults. Obese female children (n=5, age 9.0±2.1yrs) and healthy male adults (n=5, age 25.2±9.5yrs) participated in this study. The subjects were instructed to perform walking, running and counter-movement jump separately on the force platform. The measurements of kinematic data during each movement were collected by using the VICON 460 motion analysis system. The center of pressure (COP) displacement of the ground reaction force was recorded at a frequency of 20 Hz. While the subjects were taking stationary standing position with opened eyes or closed eyes on the force platform for 30 seconds, and the total length of COP displacements was calculated. Body composition was measured by bio-impedance method. There was a significant difference between obese female children and healthy male adults in BMI (27.8±2.7 vs. 22.3±3.9, p<0.05) and %fat (43.9±5.7 vs. 17.1±7.3%, p<0.01). Mean inversion-eversion angle of the hip joint during the walking (13.0±3.4 vs. 47.1±25.1 deg., p<0.05) and anterior-posterior length of COP (34.2±5.7 vs. 46.8±6.3 mm, p<0.01) were significantly larger in the obese subjects than in the normal subjects. These results indicate a high risk of fall into the obese children during exercise. From the present results, we reconfirmed that obese female children had significantly poorer composite dynamic and static balance test scores than the healthy male adults. The present study suggested a high risk of fall into the obese children during the exercises.

Advances in Curling Game Information Analysis by Considering Starting Position.

Japanese curling teams have been recently preparing for Pyeongchang Winter Olympics in 2018. In curling, there are three factors influencing game performance: physical factor, human factor, and strategic/tactical factor. The strategic/tactical factor is considered as the most important at top level. To support the strategic/tactical factor, we proposed the concept of Curling Informatics. As the first step of Curling Informatics we developed a digital scorebook iCE for digital collection of game information, storing it in a database and performing further analysis to improve player performance. In this article, we further contribute to this project by analyzing game information of world national top level teams. We have previously confirmed that correlation between shot accuracy and game score could differ with the team level or position. We also found out that selected tactics and psychological pressure on opponent team has impact on game result. However, previous analyses disregarded the order of teams in play, which could result in confusion of strategic tendencies or play characteristics. In this paper, we carried out analysis of correlations of shot scores considering whether the teams started as the first or the second. We did this to specify the process of how the team strategy/tactics influences game results.

Analysis of Curling Team Strategy and Tactics using Curling Informatics

The 2015-2016 season became a historic season for Japanese curling. Japan national curling team has won a silver medal for the first time at the 46th Women’s World Championship 2016 in Canada. However, it is still necessary to work on strengthening the team performance in order to aim for the top. Such strengthening needs to include material factors such as the physical factor and the human factor, but also the strategic/tactical factor which is crucial in curling. Bradley (2009) points out the strategic/tactical factor as the most important at top level. As an example of a research aimed at supporting such strengthening of the strategic/tactical factor, Masui et al. (2016) proposed the concept of Curling Informatics. They built an environment for strategic/tactical support which makes use of ICT by allowing digitally collect and analyze game informations in real time. Specifically, as the first step of implementation they developed a digital scorebook iCE as a method for digital collection of game information for further analysis. In this research we analyzed game information collected with iCE to establish the effective analysis for tactical support and verify the knowledge which can be obtained empirically and what kind of new knowledge can be obtained from it. We report on the new knowledge we obtained regarding the relationship between shot accuracy and difference in game scores, and difference in correlation for each level in 93 games collected during the 2013-2014 season.

OXYGEN UPTAKE IN SNOW SHOVELING WITH MODIFIED SHOVEL

INTRODUCTION Snow shoveling in the winter is hard manual labor in cold, northern regions, in most of which society is aging. For the elderly people the task is considered a physically intensive activity, associated with local muscle pain of the lower back. It was confirmed that the amount of stooping and squatting were reduced when using a modified shovel with a second handle. Additionally, less oxygen uptake was observed when using the modified shovel [1]. This study compared oxygen uptake during the shoveling of snow between a regular shovel and a modified shovel to determine how the second handle on the shovel shaft affects the oxygen demand during the shoveling in elderly subjects.

THE COMPARISON OF EMG ACTIVITIES BETWEEN KINAESTHETICS AND NORMAL METHODS DURING PATIENT-HANDLIMG TASKS IN HEALTH CARE WORKERS

INTRODUCTION A high prevalence rate of low-back pain (LBP) is found among health care workers (HCW). Compared to other jobs with heavy lifting tasks and a high prevalence rate of LBP. This may indicate that the risk in connection with a single personal handling situation is higher than the risk in connection with lifting. Several of these risk factors are present in patient-handling tasks. Biomechanical studies have estimated the load on the low back in several patient-handling tasks. Recently, the kinaesthetics method was developed in Germany. This method can reduce the mechanical load of HCW in patient-handling task. Becouse it was the result of our application of the research findings of the science of Feedback Control Theory to problems of human functions. The purpose of present study was to investigate the activities of muscles during kinaesthetics or normal method patient-handling tasks in HCW using electromyography (EMG). METHODS Twelve female subjects volunteered to participate in the laboratory experiments. The mean values ± SD of their heights, weights, and ages were 1.72 ± 0.05 m, 65.2 ± 8.9 kg, 23.2 ± 7.8 yrs., respectively. They received an explanation of the experimental protocol and provided informed consent prior to testing. None of the subjects experienced low-back pain on the experimental day. In a laboratory set-up they performed two different patient-handling tasks in randomized order. The electromyography (EMG) system (WEB-5000, Nihon Kohden, Japan) was used to collect muscle activities from the biceps brachii (BB), triceps brachii (TB), rectus abdominis (RA), erector spinae (ES), hamstrings (HA), vastus lateralis (VL), gastrocnemius (GA). and tibialis anterior. The EMG signals were amplified and recorded by a computer via A/D converter. Before carrying out the tasks, EMG was measured when the subjects performed three different isotonic contractions for arm curl, dead lift and squat. The highest obtained EMG value during these contractions, IEMGmean, was used to normalise the EMG registrations during the tasks. Immediately after completion of each patient-handling task, the subject was asked to rate her perceived physical exertion (RPE) on the low back by answering the question ‘how did you perceive the exertion on the low back’. The Borg CR10 scale (Borg, 1990), where 0 implies ‘nothing at all’ and 10 implies ‘extremely strong’ perceptual intensity, was used for the rating. All values are expressed as means ± SEM. A Student’s paired t-test was used to determination differences between the kinematic variables when using either the kinaesthetics and normal methd. Probability values of p < 0.05 were accepted as being statistically significant. RESULTS AND DISCUSSION Figure 1 shows the change of IEMGmean when the subjects performed kinaesthetics and normal method on patient-handling tasks in randomized order. IEMGmean, in BB, TB, ES, HA, GA and TA were significant difference in kinaesthetics method lower than normal one during patient-handling tasks in HCW. The decrease of the muscular activity of ES could be contributed to the LBP prevention of the nurse. Figure 2 shows change of the Borg CR10 scale when the subjects performed kinaesthetics and normal method on patient-handling tasks in randomized order. The Borg CR10 scale was significantly er kinaesthetics method than normal one. These results indicated that the patient-handling tasks in HCW affect lifting method. The kinaesthetics was a method for contributing to the reduction in the body of the HCW. CONCLUSIONS The kinaesthetics method was decreased EMG activity and muscle fatigue during patients lifting in bed. Thus, in this study kinaesthetics method may be reduced LBP in patient-handling tasks in HCW.