巻号一覧
61 巻, 3 号
選択された号の論文の13件中1～13を表示しています
- |<
- <
- 1
- >
- >|
総説
-
上條 義一郎, 池川 茂樹, 能勢 博2012 年 61 巻 3 号 p. 279-288
発行日: 2012/06/01
公開日: 2012/06/15
ジャーナル フリーHypovolemia and hyperosmolality due to thermal dehydration suppress thermoregulatory responses of sweating and cutaneous vasodilation in humans, resulting in increasing a risk of heat illness. Recently, we found in young and older subjects that an ingestion of carbohydrate-protein supplement immediately after a bout of exercise during training accelerated an increase in plasma volume and an improvement of thermoregulatory responses. These results suggest that change in plasma volume alters cutaneous vasodilation and sweat rate through baroreflexes; however, no electrical signals in the efferent path of the reflex loop have not been identified. We have recently successfully recorded skin sympathetic nerve signal components synchronized and non-synchronized with cardiac cycles, separately, in passively heated young subjects, and found that although both components increased with cutaneous vasodilation and sweat rate in hyperthermia, an increase in synchronized component was suppressed by hypovolemia with suppressed cutaneous vasidilation, while an increase in non-synchronized component was not suppressed as sweat rate. On the other hand, we found that hyperosmolality suppressed the increases of both components with suppressed cutaneous vasodilation and sweat rate. These results suggest that a synchronized component controls cutaneous vasodilation while a non-synchronized component controls sweat rate, and also that beat-by-beat changes in atrial pressure due to a fluctuation of venous return to the heart varies cutaneous vasodilation through baroreflexes but not sweat rate.抄録全体を表示PDF形式でダウンロード (1980K) -
古市 泰郎, 増田 和実2012 年 61 巻 3 号 p. 289-296
発行日: 2012/06/01
公開日: 2012/06/15
ジャーナル フリーIn skeletal muscle, carnitine is essential for the translocation of long-chain fatty-acids into the mitochondrial matrix for subsequent β-oxidation, and in the regulation of the mitochondrial acetyl coenzyme A/ free coenzyme A ratio by buffering excess acetyl groups. Based on the concept that increased carnitine availability is beneficial to skeletal muscle metabolic process, a large amount of research was directed towards investigating the effects of carnitine supplementation on exercise performance. However, it has been debated about contribution of carnitine for energy metabolism in skeletal muscle and whether carnitine supplementation can improve physical performance in healthy subjects. Recently, in order to resolve the issues, attention has been focused on the carnitine transport mechanism across the skeletal muscle plasma membrane. Due to lack of endogenous synthesis of carnitine in myocytes, skeletal muscles need to import this molecule from blood, suggesting that muscle carnitine uptake is most likely the limiting factor to muscle carnitine availability. It has been established that the specific carnitine transporter, OCTN2, is expressed in skeletal muscles and is assumed to transport carnitine into myocytes. Carnitine uptake capacity via the OCTN2, therefore, has been assumed to be one of the important factors to the skeletal muscle energy metabolism. The purpose of the review is to summarize the role of carnitine in skeletal muscle metabolism, and the current knowledge regarding the effect of carnitine supplementation of exercise performance. Furthermore, we summarize recent observations related to the carnitine transport mechanism in skeletal muscles including contribution of OCTN2 during muscle contraction.抄録全体を表示PDF形式でダウンロード (1372K) -
和田 正信, 山田 崇史, 松永 智2012 年 61 巻 3 号 p. 297-306
発行日: 2012/06/01
公開日: 2012/06/15
ジャーナル フリーRepeated contractions of skeletal muscle cause fatigue, as manifested by a reduced ability to produce force and slowed contraction. During studies of muscle fatigue, a phenomenon known as low-frequency fatigue (LFF) was observed in human skeletal muscles. It is characterized by a greater loss of force in response to low- versus high-frequency muscle stimulation and a long period of time for full recovery. This force deficit is most likely to be owing to disturbances in sarcoplasmic reticulum (SR) Ca2+ release and/or reductions in myofibrillar Ca2+ sensitivity. Studies on metabolites have implied that inorganic phosphate and Mg2+ might have some role in reduced SR Ca2+ release that occurs immediately after fatiguing contraction. In addition, recent experiments have shown that impaired myofibril function may relate to increased nitric oxide and hydroxyl radical production, whereas deterioration of SR function may be attributable to increased superoxide production, elevation of cytoplasmic Ca2+ concentration and/or decreased muscle glycogen. Finally, we will discuss possible proteins which are affected and contribute to the development of LFF.抄録全体を表示PDF形式でダウンロード (1387K)
原著
-
山代 幸哉, 佐藤 大輔, 吉田 拓矢, 石川 知志, 大西 秀明, 丸山 敦夫2012 年 61 巻 3 号 p. 307-312
発行日: 2012/06/01
公開日: 2012/06/15
ジャーナル フリーTaping is widely used by sports trainers to prevent injury and to protect affected sites post-injury. However, it is not clear whether taping affect the perception of somatosensory stimulation. We sought to clarify the effect of taping on somatosensory stimulation using somatosensory evoked potentials (SEPs). We recorded SEPs following transcutaneous electrical stimulation of the right medial forearm in ten healthy volunteers. SEPs were recorded from 9 electrodes on the scalp under control, elastic-taping and white-taping conditions. Subjects relaxed on a comfortable reclining seat without taping in the control condition, while they were subjected to taping along the muscle of forearm with tension (elastic-taping) and without tension (white-taping) in the taping conditions. Results showed that the peak amplitude of N140 did not differ significantly among the three conditions but the peak amplitude of P250 was significantly lower in the elastic-taping condition than control and white-taping conditions. Elastic-taping with tension along the muscles changes various afferent inputs from muscle spindle or skin, and this may affect the perception of somatosensory stimulation.抄録全体を表示PDF形式でダウンロード (1530K) -
織田 恵輔, 臼井 達矢, 上田 真也, 桂 良寛, 吉川 貴仁, 小林 茂, 藤本 繁夫2012 年 61 巻 3 号 p. 313-318
発行日: 2012/06/01
公開日: 2012/06/15
ジャーナル フリーAlthough there are a number of reported cases of increased cerebral blood flow during exercise, there are no reports on the relation between changes of blood flow during exercise and attentional function. The purpose of this study is to clarify the relation between changes of blood flow during exercise with AT intensity and attentional function, using near-infrared spectral analysis. The subjects were 10 healthy males. The research protocol was to conduct steady load exercise. We randomly conducted two invention trials: 1) an exercise/task trial in which a trail making test (TMT) was performed as an attentional assignment during steady load exercise, and 2) a rest/task trial in which TMT was performed during rest as a control. As a result, we observed the following: increase of oxy-Hb in the prefrontal cortex during AT exercise, the significant shortening of TMT during exercise from 69.1±10.2 seconds to63.2±7.2seconds, and, with further control, that the more oxy-Hb rises, the more TMT time is shortened. From these results, it is suggested that 10 minutes of exercise would improve attentional function, and furthermore, there is a possibility that increased cerebral blood flow may be involved with the improvement of attentional function.抄録全体を表示PDF形式でダウンロード (1218K) -
松原 建史, 前田 龍, 樋口 慶亮, 柳川 真美, 樋口 ゆう子, 山口 靖子, 出口 美華, 久保 邦子, 進藤 宗洋, 小池 城司2012 年 61 巻 3 号 p. 319-326
発行日: 2012/06/01
公開日: 2012/06/15
ジャーナル フリーPreviously, we have reported that age-predicted heart rate at 50%VO2max (HR@50%VO2max) is an effective index of adjusting appropriate exercise intensity for health promotion exercise. Thus, the aim of this study is to elucidate the change in HR at double product break point (HR@DPBP) and the validity of HR@50%VO2max due to improvement of cardiovascular fitness. Ninety two healthy adults (57 +/- 9 years old), who participated in the health exercise training course, were studied. Participants were instructed how to control the intensity of physical activity for DPBP during their daily life. DPBP was determined with the use of incremental exercise test, and METs at DPBP (METs@DPBP), HR@DPBP, ratings of perceived exertion at DPBP (RPE@DPBP) were measured before and after the course. HR@50%VO2max was calculated with the following formula; 138 - age/2 (bpm). METs@DPBP significantly increased (p<0.001) after 10 weeks of the course, whereas HR@DPBP did not change. Interestingly, however, there was a significantly positive correlation (p<0.001) between amount of change in METs@DPBP and that in HR@DPBP (ΔHR@DPBP). Multiple linear regression analysis indicated this correlation was independent from sex, age and amount of change in HR at rest (p<0.001). Before and after the course, proportion of study subjects’ %ΔHRs ((HR@50%VO2max - HR@DPBP) / HR@DPBP x 100) within -10% ~ +10% were both 48.9%, and proportion of study subjects’ RPEs@DPBP within 11~13 were 92% and 85%, respectively. In this study, it was identified that significantly positive relation between amount of change in cardiovascular fitness and that of ΔHR@DPBP. This finding was independent from potentially affecting factors. In conclusion, this longitudinal study could suggest that HR@50%VO2max and RPE were valuable indexes of determining exercise intensity for health promotion exercise.抄録全体を表示PDF形式でダウンロード (1244K) -
大須賀 洋祐, 藪下 典子, 金 美芝, 清野 諭, 鄭 松伊, 大久保 善郎, 根本 みゆき, 松尾 知明, 田中 喜代次2012 年 61 巻 3 号 p. 327-334
発行日: 2012/06/01
公開日: 2012/06/15
ジャーナル フリーThe purpose of this study was to examine the association between the hierarchy of higher-level functional capacity (instrumental self-competence, intellectual activity, social role) and the quantity of physical activity in older women (n = 175, 72.1 ± 5.8 years). Physical activity was estimated with a uniaxial accelerometer that calculated light-intensity physical activity (LPA), and moderate-to vigorous-intensity physical activity (MVPA). Higher-level functional capacity was assessed with the Tokyo Metropolitan Institute of Gerontology (TMIG) index of competence. According to the three subscales (instrumental self-competence, intellectual activity, and social role) of the TMIG index, participants who reported a score of 1 or more below the respective full marks were categorized as a group with reduced status. Logistic regression analysis was conducted to examine association between the hierarchy of higher-level functional capacity and the quantity of physical activity divided by intensity of activity, adjusted by covariance. Only low MVPA showed a significantly lower odds ratio than high MVPA in reduced status of instrumental self-competence. Since instrumental self-competence was significantly related with only the quantity of MVPA, it may be more important to focus on “quantity” of physical activity to prevent reductions in higher-level functional capacity in advanced stages of declining functional capacity.抄録全体を表示PDF形式でダウンロード (1156K) -
西脇 雅人, 栗山 晃徳, 池上 由美, 中嶋 名菜, 松本 直幸2012 年 61 巻 3 号 p. 335-341
発行日: 2012/06/01
公開日: 2012/06/15
ジャーナル フリーThis study aimed at clarifying the effects of a lifestyle intervention using an activity monitor with game functions on daily physical activity. A 12-week randomized crossover study was conducted in 23 healthy volunteers (31 ± 11 yrs). The subjects were randomly assigned to Group A (a 6-week game intervention and then a 6-week normal intervention) and Group B (a 6-week normal intervention and then a 6-week game intervention). In the game intervention period (G), the subjects wore two different activity monitors, namely a normal activity monitor (Lifecorder EX) and an activity monitor with game functions (Yuuhokei). On the other hand, in the normal intervention period (N), the subjects wore only a normal activity monitor. Daily steps were significantly higher in the G than in the N (G: 10417 ± 2358 vs. N: 8744 ± 2180 steps/day, P < 0.001). Amount of physical activity (i.e., daily total METs · hour = Ex/day) at the intensity of 3 METs or more was significantly higher in the G than in the N (G: 3.1 ± 0.9 vs. N: 2.4 ± 0.8 Ex/day, P < 0.001). Our results indicate that the lifestyle intervention using an activity monitor with game functions would more effectively increase daily physical activity such as steps and physical activity amount, than a normal intervention using an activity monitor. These findings therefore have important implications for reaching more easily the goals (i.e., 23 Ex/week or 10,000 steps/day) and the use of an activity monitor with game functions in the field of exercise or physical activity instructions.抄録全体を表示PDF形式でダウンロード (2963K) -
安田 貢, 佐藤 美理, 安藤 大輔, 鈴木 孝太, 近藤 尚己, 山縣 然太朗2012 年 61 巻 3 号 p. 343-350
発行日: 2012/06/01
公開日: 2012/06/15
ジャーナル フリーIn recent years, physical inactivity among children or adolescents has been a major public health concern. Although a number of studies have examined the effect of physical inactivity on depressive symptoms in adults, only few studies have examined this effect on children. Therefore, the purpose of this study was to examine the effect of physical activity on the development of depressive symptoms in children by using longitudinal data. The study participants were students in grades 4 to 8 in the Koshu City. Their physical activity and depressive symptoms were examined in 2008 by a questionnaire. One year later, their depressive symptoms were examined again. Students who had depressive symptoms at the baseline were excluded. Physical activity at the baseline was categorized into 3 groups as independent variables. The development of depressive symptoms was used as the dependent variable. Multivariate logistic regression analyses were performed to examine the relationship. At the baseline, 1532 students completed the questionnaire. Of them, 1379 students (727 boys and 652 girls) did not have depressive symptoms. One year later, 1319 students (95.6%) completed the questionnaires on depressive symptoms. Of them, 41 (6.0%) boys and 68 (10.6%) girls had developed depressive symptoms during the study period. High physical activity was significantly associated with decreased incidence of depressive symptoms compared to low physical activity only in boys (odds ratio: 0.37, 95% confidence interval: 0.12-0.95). Our results suggest that high physical activity significantly affects the depressive symptoms in boys.抄録全体を表示PDF形式でダウンロード (1084K) -
柏木 悠, 船渡 和男2012 年 61 巻 3 号 p. 351-363
発行日: 2012/06/01
公開日: 2012/06/15
ジャーナル フリーIn order to quantify the plantar load distribution during dynamic human movement, integrated system consisted of a pressure plate, motion capture system and a force platform was constructed and examined its accuracy and validity based on foot anatomical measurement points during take-off phase in vertical jump. Foot Scan (Rs Scan,200Hz), VICON (Oxford,100Hz) and Force plate (Kistler,1KHz) were systematically synchronized as to identify each sub-area of plantar from anatomical measurement points on foot. Each five sub-area of plantar was determined by using the methods of Stebbins et al. (2005). Accuracy and validity of plantar load and the position of center of pressure (COP) were examined by % Difference and RMS error with comparison to those obtained from Force plate, Foot Scan and VICON coordinate system. Using this system, twelve subjects performed maximum counter movement vertical jump and instantaneous plantar load changes for each of five sub-area were quantified during weighing phase during take-off. % Differences in plantar load value between Force plate and Foot Scan were less than 2.3 ± 1.5 % as well as RMS errors of COP’s position were ranged from 1.5 - 8.9 mm. Medial forefoot plantar load fairly contributed to Force plate data and peak value of plantar load in each sub-area appeared as order from Heel, Lateral forefoot and Medial forefoot. This newly developed system could quantify each plantar sub-area load with both enough accuracy and validity and also demonstrate instantaneous each sub-area’s plantar load pattern during dynamic movement such as take-off phase in vertical jump.抄録全体を表示PDF形式でダウンロード (6375K)
教育講座
-
篠原 稔2012 年 61 巻 3 号 p. 365-368
発行日: 2012/06/01
公開日: 2012/06/15
ジャーナル フリーPublishing scientific papers in English is a major part of professional activities for researchers in the biomedical field. This is because new knowledge becomes most valuable when shared with people around the world, whereas papers written in a local language are difficult to be shared with. Unfortunately, the style of scientific writing is often critically unsatisfactory in manuscripts written in English by researchers who use English as a second language. These researchers are strongly encouraged to learn essential aspects of writing scientific papers in English. To foster the ability for writing scientific papers, young researchers outside of English-speaking countries should be encouraged to take a hands-on education in scientific writing and reviewing in English, and discouraged to publish papers and books in a local language. Increased availability of hands-on education by qualified researchers would be urged for strengthening research capabilities in the biomedical field.抄録全体を表示PDF形式でダウンロード (916K)
抄録
-
2012 年 61 巻 3 号 p. 369-376
発行日: 2012年
公開日: 2012/06/15
ジャーナル フリーPDF形式でダウンロード (1490K)
記事
-
2012 年 61 巻 3 号 p. 377-381
発行日: 2012年
公開日: 2012/06/15
ジャーナル フリーPDF形式でダウンロード (1053K)
- |<
- <
- 1
- >
- >|