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1.
Ayako Higashihara Yasuharu Nagano Kazumasa Takahashi Toru Fukubayashi 《Journal of sports sciences》2015,33(13):1366-1375
This study aimed to investigate the effects of forward trunk lean on hamstring muscle kinematics during sprinting. Eight male sprinters performed maximal-effort sprints in two trunk positions: forward lean and upright. A three-dimensional musculoskeletal model was used to compute the musculotendon lengths and velocity of the biceps femoris long head, semitendinosus, and semimembranosus muscles during the sprinting gait cycle. The musculotendon lengths of all the three hamstring muscles at foot strike and toe-off were significantly greater during the forward trunk lean sprint than during the upright trunk sprint. In addition, a positive peak musculotendon lengthening velocity was observed in the biceps femoris long head and semimembranosus muscles during the late stance phase, and musculotendon lengths at that instant were significantly greater during the forward trunk lean sprint than during the upright trunk sprint. The present study provides significant evidence that a potential for hamstring muscle strain injury involving forward trunk lean sprinting would exist during the stance phase. The results also indicate that the biceps femoris long head and semimembranosus muscles are stretched during forward trunk lean sprinting while contracting eccentrically in the late stance phase; thus, the elongation load on these muscles could be increased. 相似文献
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We compared the reading development of 77 deaf and hard-of-hearing (DHH) Japanese children, aged 5–7 (40 females), with 139 of their hearing peers (74 females) in 2018. We assessed each group's phonological awareness (PA), grammar, vocabulary, and reading of hiragana (Japanese orthography children learn first). DHH children showed significant delays in grammar and vocabulary but only a slight delay in PA. Younger DHH children scored better than their hearing peers in reading. Although PA predicted reading for hearing children, reading predicted PA for DHH children. PA partially explained grammar skills for both groups. The results suggest educational intervention for reading acquisition should be based on not only general linguistic features but also each language's unique characteristics. 相似文献
3.
Chie Takahashi 《Compare》2008,38(1):5-22
This paper examines the quality and development of relations between organisations and the ways in which these are informed by incidental learning experiences in two projects. The paper conceptualizes instances of inter‐organisational learning (IOL) applying theories such as principal‐agent, prisoners' dilemma and women's place in community development. The main results are (a) that IOL can be used to maintain and modify relations of control and dominance in partnership hierarchies; (b) that IOL serves as a spin‐off of horizontal relationships and can be increased or reduced in the competition between partners for resources and identity; and (c) that IOL at the community level, when delivering outsiders' intervention, can be promoted by involving local authorities and operating within the existing household hierarchy. The paper shows that the influential role of individuals, beyond organisational boundaries, becomes critical through social networks and the establishment of trust‐based relations and resistance to learning as consequences of personal conflict. However, structural constraints in the aid system, such as asymmetric access to resources, expertise, knowledge, status and networks, ultimately determine the quality of funding management schemes and the emergence of an environment that stimulates mutual individual learning, which in turn may lead to organisational learning and inter‐organisational learning. 相似文献
4.
Kazumi Masuda Nobuo Kikuhara Hideyuki Takahashi Kunio Yamanaka 《Journal of sports sciences》2013,31(10):851-858
Abstract The aim of the present study was to examine the relationships between muscle cross-sectional area (CSA) and muscular strength in terms of knee extension and flexion, hip extension and flexion, and hip abduction and adduction among well-trained soccer players. Fourteen university soccer players participated in the study, who had previously been divided into two groups based on ability (Group A: above-average ability; Group B: average ability). Maximal isokinetic and concentric muscular strength was measured in knee extension/flexion, hip extension/flexion and hip abduction/adduction using an isokinetic dynamometer at 1.57 and 4.19 rad·s?1 (3.14 rad·s?1) in both the dominant and non-dominant leg. The CSAs of the thigh, gluteus muscles and iliopsoas muscles were calculated based on magnetic resonance imaging. There was no significant difference between the two groups in muscle CSA and isokinetic strength. Although there were some statistically significant differences between the dominant and non-dominant leg in terms of CSA and strength (P<0.05–0.01), these were small and negligible. Apart from a non-significant relationship between the CSAs of the adductor muscles and hip adductor strength (r<0.26, n.s.), the CSA of the other muscle groups correlated with maximal isokinetic strength (r=0.38–0.64, P<0.05). These results suggest that no difference in muscle characteristics (in terms of muscle CSA and strength) was apparent among well-trained soccer players, even between the dominant and non-dominant leg. There is also a case that the anatomical function of a single (or group of) muscle(s) may not be reflected by the strength—CSA relationship depending on the movements (such as hip adduction-adductor muscle CSA). Thus, further studies are required to develop methods to assess neuromuscular function in relation to muscle morphology among soccer players. 相似文献
5.
Takashi Umeda Kazuhiro Suzukawa Ippei Takahashi Yousuke Yamamoto Masaru Tanabe Arata Kojima 《Journal of sports sciences》2013,31(9):897-904
Abstract To clarify the physical and mental fatigue caused by intense exercise and the relationship between the two types of fatigue, we examined changes in anthropometric and biochemical variables, neutrophil function, and the Profile of Mood States (POMS) questionnaire in 13 female university judoists attending a one-week training camp. Blood glucose, total cholesterol, haemoglobin, leukocyte count, IgG, and phagocytic activity all decreased after the training camp compared with baseline (P ≤ 0.046). Aspartate aminotransferase, lactate dehydrogenase, creatine kinase, and neutrophil oxidative burst activity increased after the training camp (P ≤ 0.007). Of the POMS scores, that for Fatigue increased after the training camp (P = 0.041) and that for Vigour decreased (P = 0.042). The changes in several POMS scores correlated with the changes in blood biochemical variables. In particular, the change in Total mood disturbance was negatively associated with changes in myogenic enzymes (P ≤ 0.032). Our results suggest that intense exercise during training camps for female judoists leads to the appearance and accumulation of mental and physical fatigue, which are related to each other. 相似文献
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Satoru Hashizume Hiroaki Hobara Yoshiyuki Kobayashi 《European Journal of Sport Science》2019,19(6):757-764
Negative work, which is mainly generated by eccentric muscle contraction, has an important influence on the associated muscle damage. Generally, mechanical parameters are determined for one side of a lower extremity on the assumption of negligible between-limb differences. However, between-limb differences in the negative work of lower extremity joints during running remain unclear. This study examines between-limb differences in negative work and associated mechanical parameters during the contact phase of running. Twenty-five young adult males voluntarily participated in this study. Each participant was asked to run on a straight runway at a speed of 3.0?m?s?1. Negative work, amplitude, duration of negative power, moment, and angular velocity were computed for both sides of the lower extremities. Significant differences were found in negative work between limbs for the hip (18.9?±?11.7%), knee (13.6?±?10.4%), and ankle (11.8?±?8.5%) joints. For the hip joint, asymmetric negative work was attributable to the between-limb difference in the amplitude of negative power owing to a corresponding difference in the moment. The between-limb differences concerning the duration and amplitude of negative power could explain the asymmetric negative work in the knee joint. The asymmetric negative work of the ankle joint was attributable to the between-limb difference in the amplitude and duration of the negative power and the moment. These results indicate that asymmetric negative work was generated in each lower extremity joint; however, the major mechanical parameters corresponding to the negative work are not the same across the joints. 相似文献
8.
Taishi Tsuji Satoru Kanamori Masashige Saito Ryota Watanabe Yasuhiro Miyaguni Katsunori Kondo 《Journal of sports sciences》2020,38(4):422-429
ABSTRACTOlder people who engage in sports and exercise in a group render greater benefits for socio-psychological aspects compared to exercising alone. The aim of this study was to identify the prevalence of specific types of sports and exercise groups and the association with self-rated health, depressive symptoms, and frequency of laughter among community-dwelling older people. We used cross-sectional data from the 2016 Japan Gerontological Evaluation Study and analysed 63,465 males and 68,497 females aged ≥65 years. The top three most popular types among males were golf (11.3%), walking (8.4%), and ground golf (6.3%). Among females, the top three were fitness exercises (13.8%), walking (8.3%), and weight exercises (6.2%). After adjusting for potential confounders, engaging in golf with a group was significantly related with excellent self-rated health (prevalence ratio, PR, 1.31 in male and 1.78 in female), low depressive symptoms (PR, 0.70 and 0.71), and a high frequency of laughter (PR, 1.12 and 1.13). Among females, walking displayed a significant relationship with all three characteristics (PR, 1.23, 0.79, and 1.06, respectively). Golf in older males and walking in older females might be the first choice for an effective programme to spread sports and exercise groups within the older Japanese community. 相似文献
9.
Verónica S. Valentinuzzi Daniel E. Kolker Martha Hotz Vitaterna Elenice A. M. Ferrari Joseph S. Takahashi Fred W. Turek 《Learning & behavior》2001,29(2):133-142
We examined context-dependent and tone-cued fear conditioning during the activity and rest periods of C57BL/6J mice. Wheel-running activity was measured continuously as a marker of circadian phase. To control the effects of light on the response, the animals were kept in a skeleton photoperiod (two 15-min light pulses per day, indicating the beginning and the end of the day). Half the animals were trained and tested for context-dependent fear conditioning 2 h after the morning light pulse; the other half were trained and tested 2 h after the evening light pulse. Animals were tested every 24 h for 5 days to analyze the conditioned response and the rate of extinction. They were then trained for tonecued fear conditioning at the same time and tested for 5 consecutive days. A significant difference between the morning and the evening groups was observed in the conditioning level and extinction rate of context-dependent fear conditioning, but not in tone-cued fear conditioning. These results suggest a modulating effect of the biological clock on the context fear-conditioning pathway. 相似文献
10.
Yasuharu Nagano Ayako Higashihara Kazumasa Takahashi Toru Fukubayashi 《Journal of sports sciences》2013,31(18):1722-1728
AbstractWe aimed to demonstrate the changes over time in the lengths and forces of the muscles crossing the hip joint during overground sprinting and investigate the relationships between muscle lengths and muscle–tendon unit forces – particularly peak biceps femoris force. We obtained three-dimensional kinematics during 1 running cycle from 8 healthy sprinters sprinting at maximum speed. Muscle lengths and muscle–tendon unit forces were calculated for the iliacus, rectus femoris, gluteus maximus, and biceps femoris muscles of the target leg as well as the contralateral iliacus and rectus femoris. Our results showed that during sprinting, the muscles crossing the hip joint demonstrate a stretch-shortening cycle and 1 or 2 peak forces. The timing of peak biceps femoris force, expressed as a percentage of the running cycle (mean [SD], 80.5 [2.9]%), was synchronous with those of the maximum biceps femoris length (82.8 [1.9]%) and peak forces of the gluteus maximus (83.8 [9.1]%), iliacus (81.1 [5.2]%), and contralateral iliacus (78.5 [5.8]%) and also that of the peak pelvic anterior tilt. The force of the biceps femoris appeared to be influenced by the actions of the muscles crossing the hip joint as well as by the pelvic anterior tilt. 相似文献