Journal of Physical Fitness and Sports Medicine最新文献_第10页

Transcranial direct current stimulation of primary motor cortex modulates post-contraction potentiation 经颅直流电刺激初级运动皮层调节收缩后增强

Journal of Physical Fitness and Sports Medicine Pub Date : 2021-01-25 DOI: 10.7600/JPFSM.10.13

Tomoya Ishii, S. Sasada, Shinya Suzuki, T. Komiyama

{"title":"Transcranial direct current stimulation of primary motor cortex modulates post-contraction potentiation","authors":"Tomoya Ishii, S. Sasada, Shinya Suzuki, T. Komiyama","doi":"10.7600/JPFSM.10.13","DOIUrl":"https://doi.org/10.7600/JPFSM.10.13","url":null,"abstract":"Surface electromyographic activity (sEMG) of the biceps brachii (BB) during weak elbow flexion has been reported to immediately increase after strong elbow flexion even while exerting consistent force; this phenomenon is called “post-contraction potentiation” (PCP). To determine whether the central nervous system is involved in PCP, we investigated the effect of transcranial direct current stimulation (tDCS) and transcranial magnetic stimulation (TMS) of the primary motor cortex (M1) during PCP. Initially, the participants were instructed to perform successive muscle contraction tasks with different forces: 2% (Test 1); then 25%, 50%, or 100% (conditioning contraction [CC]); and again 2% (Test 2) of maximum voluntary contraction (MVC). In subsequent experiments, the CC intensity was set at 50% MVC, and tDCS (anodal, cathodal, and sham) was applied to the M1 before the task. In the last experiment, TMS was applied to M1 to evaluate the excitability of the corticospinal tract during Tests 1 and 2. The CC intensity at 50% or 100% MVC generated PCP, but didn’t at 25% MVC. Anodal tDCS significantly decreased the magnitude of PCP, while cathodal tDCS showed an increase in magnitude compared to sham tDCS. The BB motor-evoked potential amplitude during Test 2 was lower compared to that during Test 1. These findings suggest that changes in the excitability of the corticospinal tract and resultant changes in the activation pattern of motor unit activity play a role in generating PCP.","PeriodicalId":55847,"journal":{"name":"Journal of Physical Fitness and Sports Medicine","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-01-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42136447","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

Effect of pre-season training camp on oral immune functions in elite collegiate volleyball players 季前训练营对高校优秀排球运动员口腔免疫功能的影响

Journal of Physical Fitness and Sports Medicine Pub Date : 2021-01-25 DOI: 10.7600/JPFSM.10.39

Ryota Sone, Kenji Yamamoto, K. Ohishi

{"title":"Effect of pre-season training camp on oral immune functions in elite collegiate volleyball players","authors":"Ryota Sone, Kenji Yamamoto, K. Ohishi","doi":"10.7600/JPFSM.10.39","DOIUrl":"https://doi.org/10.7600/JPFSM.10.39","url":null,"abstract":"In various sports, high-intensity training reduces the oral immune function of the player. The effect of volleyball training camp on salivary immune function is unclear. This study aimed to investigate the effect of pre-season training on salivary immune function in elite collegiate volleyball players. Twenty-one elite collegiate volleyball players (mean age: 19.6 ± 1.1 years, mean height: 185.2 ± 7.8 cm) participated in this observational study. Saliva samples were taken on Day-1 (First day) and Day-11 (Final day) during pre-season training camp. Fatigue was measured using a VAS (visual analog scale) every day during the training camp period. Oral immune function was assessed in terms of secretory immunoglobulin A (s-SIgA) secretion rate and nitric oxide (s-NO) secretion rate. The s-NO secretion rate showed no significant change from Day-1 (0.69 ± 0.49 µmol/min) to Day-11 (0.56 ± 0.33 µmol/min). How-ever, the s-SIgA secretion rate on Day-11 (28 ± 16 µg/min) was significantly lower (P < 0.05) than that on Day-1 (35 ± 18 µg/min). Changes in fatigue scale scores positively correlated with changes in s-NO secretion rate ( r s = .591, P < 0.01), but not with changes in s-SIgA secretion rate ( r s = .411, P = 0.06). In this study, the concentration of s-NO stored frozen was determined, but the effect of the storage method on s-NO should be investigated in future studies. In conclu-sion, pre-season volleyball training camp may affect oral immune function as in other sports.","PeriodicalId":55847,"journal":{"name":"Journal of Physical Fitness and Sports Medicine","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-01-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47227392","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Lifestyle and health 生活方式与健康

Journal of Physical Fitness and Sports Medicine Pub Date : 2020-11-25 DOI: 10.7600/jpfsm.6.525

Vlasta Hrabak Žerjavić, V. Kralj, M. Kuzman

引用次数: 0

Nutrition and digestion 营养与消化

Journal of Physical Fitness and Sports Medicine Pub Date : 2020-11-25 DOI: 10.7600/jpfsm.6.468

Susanna Cocroft

引用次数: 22

Influence of obesity on skeletal muscle contractile dysfunction in aging 肥胖对老年人骨骼肌收缩功能障碍的影响

Journal of Physical Fitness and Sports Medicine Pub Date : 2020-09-25 DOI: 10.7600/jpfsm.9.199

Hiroaki Eshima

引用次数: 2

Descriptive epidemiology of injuries in Japanese male collegiate rugby union players 日本男子大学橄榄球联盟运动员损伤的描述性流行病学

Journal of Physical Fitness and Sports Medicine Pub Date : 2020-09-25 DOI: 10.7600/jpfsm.9.223

R. Ogaki, Gento Otake, Satoko Nakane, Y. Kosasa, Y. Kanno, Ayane Ogura, M. Takemura

{"title":"Descriptive epidemiology of injuries in Japanese male collegiate rugby union players","authors":"R. Ogaki, Gento Otake, Satoko Nakane, Y. Kosasa, Y. Kanno, Ayane Ogura, M. Takemura","doi":"10.7600/jpfsm.9.223","DOIUrl":"https://doi.org/10.7600/jpfsm.9.223","url":null,"abstract":"To the best of our knowledge, most previous studies regarding the epidemiology of injuries in rugby union (rugby) players have focused on professional players. Therefore, data on injuries in collegiate rugby players in Japan is limited. The purpose of this study was to conduct a prospective injury survey of Japanese male collegiate rugby players over several years and to analyze the injuries that occurred during matches and training according to field position, type of injury, and mechanism of injury. This prospective study initially registered 128 rugby players from one university club. The occurrence of injuries was recorded by athletic trainers during the rugby seasons between 2017 and 2019. The total injury rate (IR) was 7.26 injuries/1000 player-hours (1000 PHs). The match IR (122.73 injuries/1000 PHs) was almost 31.9 times higher than the training IR (3.84 injuries/1000 PHs). Ankle sprains/ligament injuries (17.7%; 1.28 injuries/1000 PHs) were the most common injuries, in addition to acromioclavicular joint injuries in forwards and hamstring strain injuries in backs. The most common injury mechanism was tackling (16.4%). Injury characteristics differed according to field position; therefore, preventive measures according to field position are necessary. Moreover, the high number of tackle injuries suggests that improved tackle skills would help reduce injuries. The IR among Japanese collegiate rugby players was higher than that reported previously. Injury prevention training for collegiate players is necessary to reduce the number of injuries.","PeriodicalId":55847,"journal":{"name":"Journal of Physical Fitness and Sports Medicine","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49342242","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Effects of voluntary exercise on plasma and urinary metabolites and gut microbiota in mice fed with high-fat-diet 自愿运动对高脂饮食小鼠血浆和尿液代谢产物及肠道微生物群的影响

Journal of Physical Fitness and Sports Medicine Pub Date : 2020-09-25 DOI: 10.7600/JPFSM.9.205

C. Watanabe, Nanako Kobiki, Takafumi Aoki, M. J. Kremenik, T. Nagano, H. Yano, Eri Oyanagi

{"title":"Effects of voluntary exercise on plasma and urinary metabolites and gut microbiota in mice fed with high-fat-diet","authors":"C. Watanabe, Nanako Kobiki, Takafumi Aoki, M. J. Kremenik, T. Nagano, H. Yano, Eri Oyanagi","doi":"10.7600/JPFSM.9.205","DOIUrl":"https://doi.org/10.7600/JPFSM.9.205","url":null,"abstract":"The aim of this study was to examine the effects of voluntary exercise on plasma and urinary metabolites and the changes in gut microbiota in mice fed with a high-fat-diet. Healthy male C57BL/6J mice (four-week-old, n = 27) were fed a normal controlled diet (CD) and a high-fat-diet (HFD) for 10 weeks under two conditions: voluntary wheel running (W) and sedentary controlled condition (C). The metabolites in the collected plasma and urine were detected using 1 H-NMR spectroscopy techniques. Also, 16S-rRNA gene next-generation sequencing was carried out on the collected feces. Wheel running activity in HFDW mice was slightly higher than that in CDW mice (p = 0.075). Exercise and diet significantly altered body weight, fat accumulation, and glucose tolerance tests. In plasma, amino acids such as Leu, Ile, Ala and Tyr, were increased by exercise. Diet influenced the metabolites in both the plasma and urine of mice and showed signiﬁcant differences; in plasma, Leu, Ile, Glu, 3-HB, lactate and acetate, whereas in urine, citrate, trimethylamine (TMA), trimethylamine-N-oxide (TMAO), taurine, hippurate and allantoin. With regard to beta diversity, unweighted UniFrac analysis (principal coordinate analysis: PCoA) showed the difference between CD and HFD mice could be observed under PC1 (22.61%). Although there was substantial overlap between two conditions (C vs. W), HFD groups were positioned in a slightly different area when compared to the C and W conditions. Firmicutes/Bacteroidetes ratio, which might be associated with obesity, in HFD mice was significantly higher than that in CD mice, but not affected by wheel running. Our results suggest that testing in both plasma and urinary metabolites may prove to be a more reliable approach to quantitative metabolite analysis on the effects of exercise-dependent hosts or as an independent alteration of gut microbiota on the hosts.","PeriodicalId":55847,"journal":{"name":"Journal of Physical Fitness and Sports Medicine","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47888195","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Effects of low-intensity and short-duration isometric contraction after static stretching on range of motion, passive stiffness, and isometric muscle force 静态拉伸后的低强度和短时间等距收缩对运动范围、被动僵硬和等距肌肉力的影响

Journal of Physical Fitness and Sports Medicine Pub Date : 2020-09-25 DOI: 10.7600/jpfsm.9.247

Shin Goto, Shingo Matsuo, M. Iwata, Wakako Tsuchida, Genki Hatano, S. Kataura, Yasuhiro Banno, Y. Asai, Shigeyuki Suzuki

{"title":"Effects of low-intensity and short-duration isometric contraction after static stretching on range of motion, passive stiffness, and isometric muscle force","authors":"Shin Goto, Shingo Matsuo, M. Iwata, Wakako Tsuchida, Genki Hatano, S. Kataura, Yasuhiro Banno, Y. Asai, Shigeyuki Suzuki","doi":"10.7600/jpfsm.9.247","DOIUrl":"https://doi.org/10.7600/jpfsm.9.247","url":null,"abstract":"Although static stretching is commonly performed to improve flexibility, it has been reported to have detrimental effects on muscle force and performance. Previous studies have reported that low-intensity and short-duration isometric contraction after static stretching inhibits stretch-induced force loss. However, the detailed effects of low-intensity short-duration isometric contraction after static stretching on flexibility, such as passive torque and stiffness, are currently unclear. Therefore, the current study sought to reveal the effects of low-intensity and short-duration isometric contraction after static stretching on flexibility and muscle force. Sixteen healthy participants (eight men, eight women) performed 300-s static stretching (SS), 300-s static stretching followed by 6-s 30% maximum isometric voluntary contraction (MIVC) (SS-30% MIVC), and 6-s 30% MIVC (30% MIVC) of the right hamstring on three separate days, in random order. Range of motion (ROM) and passive stiffness during knee extension, peak passive torque, and MIVC torque were obtained before and after exercise. ROM and peak passive torque were significantly increased after all exercises, whereas passive stiffness and MIVC torque were significantly decreased after SS only. Moreover, ROM after SS and SS-30% MIVC were significantly greater than that of 30% MIVC, and peak passive torque after SS-30% MIVC was significantly greater than that of SS, while passive stiffness after SS was significantly lower than that of 30% MIVC. These results indicate that low-intensity and short-duration isometric contraction after static stretching is effective for inhibiting stretch-induced force loss while also inhibiting the effects of static stretching on passive","PeriodicalId":55847,"journal":{"name":"Journal of Physical Fitness and Sports Medicine","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44359757","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Effects of combined therapy of ACE inhibitor and exercise on the development of diabetic nephropathy in Otsuka Long-Evans Tokushima fatty rats ACE抑制剂联合运动治疗对大鼠糖尿病肾病发展的影响

Journal of Physical Fitness and Sports Medicine Pub Date : 2020-09-25 DOI: 10.7600/jpfsm.9.235

Shinichiro Aoyama, Daisuke Shindo, Junichi Otsuka, Eriko Matsuo, Shigeru Matsubara, Masato Suzuki

引用次数: 0

Acute effects of static passive stretching without voluntary contraction of skeletal muscles on arterial stiffness in elderly lacking exercise habits 无骨骼肌主动收缩的静态被动拉伸对缺乏运动习惯老年人动脉僵硬的急性影响

Journal of Physical Fitness and Sports Medicine Pub Date : 2020-09-25 DOI: 10.7600/jpfsm.9.217

T. Morifuji, Hidetoshi Nakao, Masashi Hashimoto, M. Imaoka, H. Fujino

{"title":"Acute effects of static passive stretching without voluntary contraction of skeletal muscles on arterial stiffness in elderly lacking exercise habits","authors":"T. Morifuji, Hidetoshi Nakao, Masashi Hashimoto, M. Imaoka, H. Fujino","doi":"10.7600/jpfsm.9.217","DOIUrl":"https://doi.org/10.7600/jpfsm.9.217","url":null,"abstract":"Stretching exercises conducted by oneself, herein referred to as self-stretching exercises, improve arterial stiffness in healthy people. Such exercises include voluntary contraction of peripheral muscles in addition to stretching of target muscles. However, the effects of static passive stretching without voluntary contraction of skeletal muscles on arterial stiffness remain unknown. In addition, it is important to verify the effects of stretching in the elderly lacking exercise habits with advanced arterial stiffness. Therefore, the purpose of the present study was to verify the acute effects of static passive stretching, without voluntary contraction of skeletal muscles, on the cardio-ankle vascular index (CAVI) in elderly individuals lacking exercise habits. The present study followed a pretest-posttest design without a control group. Twenty-nine elderly individuals (mean age, 77.8 ± 7.0 years; 24 female) recruited at an orthopedic clinic participated in the present study. The participants were subjected to static passive stretching of the neck, trunk, and extremities for 40 min by the same physical thera-pist. Stretching involved the shoulder flexors/extensors, elbow flexors/extensors, wrist palmar flexors/dorsal flexors, hip flexors/extensors/adductors, knee flexors/extensors, ankle plantar flexors/dorsal flexors, neck muscles, and trunk muscles. The CAVI (Rt, Lt, Ave), ankle-brachial index (ABI), blood pressure, and pulse rate were assessed before and after stretching. After stretching, both CAVI (Lt, Ave) and pulse rate were significantly decreased. In contrast, no significant changes in CAVI (Rt), ABI, or blood pressure were observed. The key new finding of the present study was that static passive stretching without voluntary contraction of skeletal muscles acutely improved the CAVI in elderly individuals lacking exercise habits.","PeriodicalId":55847,"journal":{"name":"Journal of Physical Fitness and Sports Medicine","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48532428","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0