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1.
Tachibana K Yashiro K Miyazaki J Ikegami Y Higuchi M 《Sports biomechanics / International Society of Biomechanics in Sports》2007,6(1):44-58
Although it is clear that rowers have a large muscle mass, their distribution of muscle mass and which of the main motions in rowing mediates muscle hypertrophy in each body part are unclear. We examine the relationships between partial motion power in rowing and muscle cross-sectional area of the thigh, lower back, and upper arms. Sixty young rowers (39 males and 21 females) participated in the study. Joint positions and forces were measured by video cameras and rowing ergometer software, respectively. One-dimensional motion analysis was performed to calculate the power of leg drive, trunk swing, and arm pull motions. Muscle cross-sectional areas were measured using magnetic resonance imaging. Multiple regression analyses were carried out to determine the association of different muscle cross-sectional areas with partial motion power. The anterior thigh best explained the power demonstrated by leg drive (r2 = 0.508), the posterior thigh and lower back combined best explained the power demonstrated by the trunk swing (r2 = 0.493), and the elbow extensors best explained the power demonstrated by the arm pull (r2 = 0.195). Other correlations, such as arm muscles with leg drive power (r2 = 0.424) and anterior thigh with trunk swing power (r2 = 0.33 5), were also significant. All muscle cross-sectional areas were associated with rowing performance either through the production of power or by transmitting work. The results imply that rowing motion requires a well-balanced distribution of muscle mass throughout the body. 相似文献
2.
Chris Mawhinney Helen Jones David A. Low Daniel J. Green Glyn Howatson Warren Gregson 《European Journal of Sport Science》2017,17(5):519-529
This study determined the influence of cold (8°C) and cool (22°C) water immersion on lower limb and cutaneous blood flow following resistance exercise. Twelve males completed 4 sets of 10-repetition maximum squat exercise and were then immersed, semi-reclined, into 8°C or 22°C water for 10-min, or rested in a seated position (control) in a randomized order on different days. Rectal and thigh skin temperature, muscle temperature, thigh and calf skin blood flow and superficial femoral artery blood flow were measured before and after immersion. Indices of vascular conductance were calculated (flux and blood flow/mean arterial pressure). The colder water reduced thigh skin temperature and deep muscle temperature to the greatest extent (P?<?.001). Reductions in rectal temperature were similar (0.2–0.4°C) in all three trials (P?=?.69). Femoral artery conductance was similar after immersion in both cooling conditions, with both conditions significantly lower (55%) than the control post-immersion (P?<?.01). Similarly, there was greater thigh and calf cutaneous vasoconstriction (40–50%) after immersion in both cooling conditions, relative to the control (P?<?.01), with no difference between cooling conditions. These findings suggest that cold and cool water similarly reduce femoral artery and cutaneous blood flow responses but not muscle temperature following resistance exercise. 相似文献
3.
KANTA TACHIBANA KAZUYA YASHIRO JUN MIYAZAKI YASUO IKEGAMI MITSURU HIGUCHI 《Sports biomechanics / International Society of Biomechanics in Sports》2013,12(1):44-58
Although it is clear that rowers have a large muscle mass, their distribution of muscle mass and which of the main motions in rowing mediates muscle hypertrophy in each body part are unclear. We examine the relationships between partial motion power in rowing and muscle cross-sectional area of the thigh, lower back, and upper arms. Sixty young rowers (39 males and 21 females) participated in the study. Joint positions and forces were measured by video cameras and rowing ergometer software, respectively. One-dimensional motion analysis was performed to calculate the power of leg drive, trunk swing, and arm pull motions. Muscle cross-sectional areas were measured using magnetic resonance imaging. Multiple regression analyses were carried out to determine the association of different muscle cross-sectional areas with partial motion power. The anterior thigh best explained the power demonstrated by leg drive (r 2 = 0.508), the posterior thigh and lower back combined best explained the power demonstrated by the trunk swing (r 2 = 0.493), and the elbow extensors best explained the power demonstrated by the arm pull (r 2 = 0.195). Other correlations, such as arm muscles with leg drive power (r 2 = 0.424) and anterior thigh with trunk swing power (r 2 = 0.335), were also significant. All muscle cross-sectional areas were associated with rowing performance either through the production of power or by transmitting work. The results imply that rowing motion requires a well-balanced distribution of muscle mass throughout the body. 相似文献
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5.
Ulysses Fernandes Ervilha Luis Mochizuki Aylton Figueira Jr. Joseph Hamill 《Journal of sports sciences》2017,35(17):1697-1703
This study aimed to investigate the activation of lower limb muscles during barefoot and shod running with forefoot or rearfoot footfall patterns. Nine habitually shod runners were asked to run straight for 20 m at self-selected speed. Ground reaction forces and thigh and shank muscle surface electromyographic (EMG) were recorded. EMG outcomes (EMG intensity [iEMG], latency between muscle activation and ground reaction force, latency between muscle pairs and co-activation index between muscle pairs) were compared across condition (shod and barefoot), running cycle epochs (pre-strike, strike, propulsion) and footfall (rearfoot and forefoot) by ANOVA. Condition affected iEMG at pre-strike epoch. Forefoot and rearfoot strike patterns induced different EMG activation time patterns affecting co-activation index for pairs of thigh and shank muscles. All these timing changes suggest that wearing shoes or not is less important for muscle activation than the way runners strike the foot on the ground. In conclusion, the guidance for changing external forces applied on lower limbs should be pointed to the question of rearfoot or forefoot footfall patterns. 相似文献
6.
南拳难度动作连接技术的生物力学分析 总被引：2，自引：0，他引：2
采用运动生物力学研究方法，分析和讨论了武术套路南拳难度动作连接难度。结果表明：提膝独立动作的失误率最高、连接难度的动动连接及动静连接技术存在差异和不同的力学特征。建议：应该注意腿部肌肉主动收缩完成着地支撑，而不是被动地着地缓冲；在难度动作完成中，动作之间具有相互帮助、相互促进和相互干扰的作用，应加强组合部分的动作训练，通过改进技术动作以减小干扰，提高动作质量；借鉴田径等其他项目的跳跃训练，提高武术运动员的跳跃能力；在南拳连接难度动作中的动动连接，第二跳的支撑腿以复合杠杆的形式完成动作，要加强支撑腿大、小腿后肌群的力量才能够满足动作力学特征的要求。 相似文献
7.
The purpose of the present study was to determine whether there is a sex difference in limb muscle cross-sectional area by comparing upper- and lower-body limb fat-free cross-sectional areas (FFCSAs) adjusted for differences in fat-free weight (FFW), in male and female athletes with similar histories of upper-body physical conditioning and in non-athletes. Limb FFCSAs were calculated from circumferences corrected for subcutaneous fat thickness and FFW was estimated from body density measured by underwater weighing in 24 male and 25 female swimmers and 23 male and 25 female non-athletes, 15 to 28 years of age. The male swimmers had 32% larger FFWs and 49% larger upper-arm, similar forearm and 23% larger thigh FFCSAs compared to the female swimmers. The male non-athletes had 34% larger FFWs, 61% larger upper-arms, 54% larger forearms and 35% larger thighs than female non-athletes. To adjust for differences in body size, analysis of covariance was performed on the FFCSAs using FFW as the covariate. For the swimmers there were no significant differences (P greater than 0.05) in the adjusted FFCSAs. For the non-athletes, males had significantly larger adjusted upper-arm and forearm FFCSAs than the females but thigh FFCSAs were not significantly different (P greater than 0.05). These results suggest that sex differences in muscle area of the arms, may be partially attributed to long-term activity differences between sexes. Possible long-term differences in activity between sexes should be considered in comparisons of functional or performance measures between sexes. 相似文献
8.
De Ste Croix MB Armstrong N Chia MY Welsman JR Parsons G Sharpe P 《Journal of sports sciences》2001,19(2):141-148
In this study, we used multi-level regression modelling to assess the influence of age, sex, body size, skinfold thicknesses, maturity, thigh muscle volume and isokinetic leg strength on the development of load- and inertia-adjusted peak (1 s) and mean power (30 s) determined using the Wingate anaerobic test. Fifteen males and 19 females were measured twice, first aged 10.0 +/- 0.3 years and then aged 11.8 +/- 0.3 years. Initial models identified body mass and height as significant explanatory variables (P < 0.05) for peak power and mean power, with an additional age effect for the former. No significant differences between the sexes or maturity effects were observed for either peak or mean power (P > 0.05). The introduction of sum of skinfolds improved the fit of the model and rendered the height term non-significant for both peak and mean power (P> 0.05). An age effect became apparent for mean power. When isokinetic leg strength and thigh muscle volume were entered into the model, the latter exerted a significant effect on both peak and mean power (P< 0.05), whereas isokinetic leg strength was not a significant explanatory variable for either (P> 0.05). In conclusion, thigh muscle volume exerts a positive influence on young people's short-term power output, which is additional to the effects of body mass, sum of skinfolds and age. 相似文献
9.
Henrik S⊘rensen Morten Zacho Erik B. Simonsen Poul Dyhre‐Poulsen Klaus Klausen 《Journal of sports sciences》2013,31(6):483-495
Fast unloaded movements (i.e. striking, throwing and kicking) are typically performed in a proximo‐distal sequence, where initially high proximal segments accelerate while distal segments lag behind, after which proximal segments decelerate while distal segments accelerate. The aims of this study were to examine whether proximal segment deceleration is performed actively by antagonist muscles or is a passive consequence of distal segment movement, and whether distal segment acceleration is enhanced by proximal segment deceleration. Seventeen skilled taekwon‐do practitioners were filmed using a high‐speed camera while performing a high front kick. During kicking, EMG recordings were obtained from five major lower extremity muscles. Based on the kinematic data, inverse dynamics computations were performed yielding muscle moments and motion‐dependent moments. The results indicated that thigh deceleration was caused by motion‐dependent moments arising from lower leg motion and not by active deceleration. This was supported by the EMG recordings. Lower leg acceleration was caused partly by a knee extensor muscle moment and partly by a motion‐dependent moment arising from thigh angular velocity. Thus, lower leg acceleration was not enhanced by thigh deceleration. On the contrary, thigh deceleration, although not desirable, is unavoidable because of lower leg acceleration. 相似文献
10.
Sunita Mathur Robert D Levy W. Darlene Reid 《Cardiopulmonary Physical Therapy Journal》2008,19(3):84-93
Purpose: Exercise limitation in recipients of lung transplant may be a result of abnormalities in the skeletal muscle. However, it is not clear whether these abnormalities are merely a reflection of the changes observed in the pretransplant condition. The purpose of this paper was to compare thigh muscle volume and composition, strength, and endurance in lung transplant recipients to people with chronic obstructive pulmonary disease (COPD).Methods: Single lung transplant recipients (n=6) and people with COPD (n=6), matched for age, sex, and BMI participated in the study. Subjects underwent MRI to determine muscle size and composition, lower extremity strength testing and an isometric endurance test of the quadriceps.Results: Lung transplant recipients had similar muscle volumes and intramuscular fat infiltration of their thigh muscles and similar strength of the quadriceps and hamstrings to people with COPD who had not undergone transplant. However, quadriceps endurance tended to be lower in transplant recipients compared to people with COPD (15 ± 7 seconds in transplant versus 31 ± 12 seconds in COPD, p = 0.08).Conclusions: Recipients of lung transplant showed similar changes in muscle size and strength as people with COPD, however muscle endurance tended to be lower in people with lung transplants. Impairments in muscle endurance may reflect the effects of immunosuppressant medications on skeletal muscle in people with lung transplant.Key Words: lung transplant, muscle function, MRI 相似文献
11.
目的:探究冷水浴对延迟性肌肉酸痛(DOMS)患者膝关节本体感觉的干预效果及作用机制。方法:采用随机对照试验,24名男性二级短跑运动员随机分为冷水浴干预组(n=12)和静坐对照组(n=12)。经离心运动诱发下肢肌群出现DOMS,静坐休息5min后进行冷水干预或静坐。分别在运动前、运动后24h、48h、72h、96h测量受试者的左大腿围度、自觉疼痛程度、左腿股四头肌最大等长肌力以及左腿膝关节本体感觉(位置觉+肌肉力觉)。在运动前、运动后即刻(0min)、5min、10min、15min分别测量血乳酸值。结果:(1)离心运动后即刻,两组大腿围度均显著性增加(P<0.05),运动后24h、48h、72h,CWI组的左大腿围度显著低于CON组(P<0.01);(2)离心运动后即刻,两组自觉疼痛程度均显著性增加,运动后24h、72h,CWI组的疼痛程度显著性低于CON组(P<0.01);(3)离心运动后即刻,两组血乳酸值均出现显著性上升(P<0.05),运动后0min~15min,两组间无显著性差异(P>0.05);(4)离心运动后即刻,两组的左腿MVIC均出现显著性下降(P<0.05),运动后24h~96h,CWI组MVIC显著高于CON组(P<0.01),(5)离心运动后即刻,两组左腿的本体感觉(主、被动位置觉、肌肉力觉)均出现显著性下降(P<0.05);运动后24h~96h,CWI组的主动位置觉显著高于CON组(P<0.01),运动后72h,CWI组的被动位置觉显著低于CON组(P<0.01),其他时间点(24h、48h、96h)无显著性差异(P>0.05),运动后24h~96h,CWI组的肌肉力觉显著高于CON组(P<0.01)。结论:冷水浴是运动训练或比赛后快速减轻DOMS症状的有效手段,有利于肌肉肿胀的恢复、减轻疼痛感、促进工作肌肉最大等长肌力及该肌肉所附着关节的本体感觉的恢复,总体有利于减轻DOMS症状。 相似文献
12.
Vivian H. Heyward Sandra M. Johannes-Ellis Jacki F. Romer 《Research quarterly for exercise and sport》2013,84(2):154-159
The purpose of this study was to examine gender differences in upper and lower body strength as a function of lean body weight and the distribution of muscle and subcutaneous fat in the upper and lower limbs. The subjects were 103 physically active men (n = 48) and women (n = 55). The peak torques produced during shoulder flexion (SF) and knee extension (KE) were used as measures of upper body and lower body strength, respectively. Flexed arm girth, thigh girth, triceps skinfold, and thigh skinfold were used to estimate the distribution of muscle and subcutaneous fat in the limbs. Results of the MANOVA revealed that the overall strength of men was significantly greater than that of women. Results of MANCOVA indicated that the SF and KE strength of women and men did not differ significantly when differences in lean body weight, arm girth, thigh girth, triceps skinfold and thigh skinfold were statistically controlled. High levels of SF and KE strength were associated with a high lean body weight and a large arm girth. Results of the multiple regression analysis indicated that for men a substantial portion of the variance in both SF and KE strength was explained by lean body weight alone; whereas strength variations in women were explained more adequately by including limb variables along with lean body weight. Within the limitations of this study, it was concluded that gender differences in upper and lower body strength are a function of differences in lean body weight and the distribution of muscle and subcutaneous fat in the body segments. Upper body strength is relatively more important than lower body strength in characterizing the gender difference in strength. 相似文献
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14.
The purpose of the study was to determine the anthropological status of elite male and female speed skaters, who were members of the 1985–7 Canadian national teams. The data were compared to those for a control group of University students. The subjects were 8 males and 6 females between 19 and 27 years of age. Nine breadth, 14 girth, 16 length and 15 skinfold measurements were used to compute parameters of body build and the composition; corrected diameters, masses, volumes and fat‐free volumes of the upper arm, forearm, thigh and calf. The speed skaters were found to be similar in body height and mass (males: 178 ± 7.6 cm and 75.5 ± 5.5 kg, females: 165.8 ± 3.8 cm and 62.3 ± 5.8 kg) to the student controls, but they had relatively and absolutely shorter legs and longer trunks. The speed skaters had a lower amount of body fat and higher FFM than their respective student controls and significantly greater relative (P ≤ 0.01) and absolute (P ≤ 0.05) total muscle mass. Analysis of composition within segments indicated that the additional muscle mass is located entirely in the lower extremity. The volume and mass of the thigh was greater (P ≤ 0.01 for the males) than that of the respective controls while the estimated volume of fat was lower. The female speed skaters were found to have more fat on their thigh than either the male speed skaters or male controls. The corrected diameter and mass of the thigh were greater (with respect to the sex) than those reported for 400 m sprinters, marathon runners, cross‐country skiers and figure skaters. The results of the initial assessment were compared to the two consecutive tests of the men's team (conducted 8 and 12 months later) and to one repeated test of the women's team (3 months later). Changes were recorded in skinfold measurements and the muscle component of the thigh. 相似文献
15.
The purpose of the study was to determine the anthropological status of elite male and female speed skaters, who were members of the 1985-7 Canadian national teams. The data were compared to those for a control group of University students. The subjects were 8 males and 6 females between 19 and 27 years of age. Nine breadth, 14 girth, 16 length and 15 skinfold measurements were used to compute parameters of body build and the composition; corrected diameters, masses, volumes and fat-free volumes of the upper arm, forearm, thigh and calf. The speed skaters were found to be similar in body height and mass (males: 178 +/- 7.6 cm and 75.5 +/- 5.5 kg, females: 165.8 +/- 3.8 cm and 62.3 +/- 5.8 kg) to the student controls, but they had relatively and absolutely shorter legs and longer trunks. The speed skaters had a lower amount of body fat and higher FFM than their respective student controls and significantly greater relative (P less than or equal to 0.01) and absolute (P less than or equal to 0.05) total muscle mass. Analysis of composition within segments indicated that the additional muscle mass is located entirely in the lower extremity. The volume and mass of the thigh was greater (P less than or equal to 0.01 for the males) than that of the respective controls while the estimated volume of fat was lower. The female speed skaters were found to have more fat on their thigh than either the male speed skaters or male controls. The corrected diameter and mass of the thigh were greater (with respect to the sex) than those reported for 400 m sprinters, marathon runners, cross-country skiers and figure skaters. The results of the initial assessment were compared to the two consecutive tests of the men's team (conducted 8 and 12 months later) and to one repeated test of the women's team (3 months later). Changes were recorded in skinfold measurements and the muscle component of the thigh. 相似文献
16.
张福祥 《哈尔滨体育学院学报》2004,22(2)
就少年短跑运动员大腿后侧肌群力量训练比重失调 ,而引起大腿力量发展不均衡 ,使运动员在比赛中肌肉易受损伤并影响运动成绩 ,进行深入的分析。指出在少年短跑训练中应高度重视对大腿后侧肌群的力量训练 ,要根据少年选手的具体情况 ,采用相应的力量训练方法与手段进行针对性训练 ,以尽快缩小大腿前后侧肌群力量的差异 ,提高肌肉力量训练的整体水平 ,为提高短跑运动成绩预防肌肉拉伤打下良好基础。 相似文献
17.
经过多年的武术带队训练和跟踪调查，发现武术训练当中引起的运动损伤大部分为大腿后部肌群Guo绳肌的拉伤，如何预防和处理Guo绳肌损伤成为提高武术水平的关键。 相似文献
18.
Kohei Watanabe Takayuki Sato Takahiro Mukaimoto Wataru Takashima Michio Yamagishi Tetsunari Nishiyama 《Journal of sports sciences》2016,34(15):1413-1422
We aimed to investigate neuromuscular activation of thigh muscles during track cycling at various speeds. Eight male competitive cyclists volunteered to participate in this study. Surface electromyography of the vastus lateralis, biceps femoris and adductor magnus muscles of the bilateral legs was recorded during track cycling on velodromes with a 250-m track. The participants were instructed to maintain three different lap times: 20, 18 and 16 s. The average rectified value (ARV) was calculated from the sampled surface electromyography. Significantly higher ARVs were observed in the right compared to left leg for the biceps femoris muscle during both straight and curved sections at 18- and 16-s lap times (P < 0.05). In the biceps femoris muscle, significant changes in ARVs during the recovery phase with an increase in speed were seen in the right leg only (P < 0.05). There were no significant differences in ARVs between the straight and curved sections for all three muscles (P > 0.05). From our findings, it was suggested that during track cycling on a velodrome the laterality of the biceps femoris muscle activity is a key strategy to regulate the speed, and fixed neuromuscular strategies are adopted between straight and curved sections for thigh muscles. 相似文献
19.
Stephan Sorichter Johannes Mair Arnold Koller Erich Muller Christian Kremser Werner Judmaier 《Journal of sports sciences》2013,31(9):687-691
The aim of this study was to examine the relationship between myosin heavy chain (MHC) release as a specific marker of slow-twitch muscle fibre breakdown and magnetic resonance imaging (MRI) of skeletal muscle injury after eccentric exercise. The effects of a single series of 70 high-intensity eccentric contractions of the quadriceps femoris muscle group (single leg) on plasma concentrations of creatine kinase and MHC fragments were assessed in 10 young male sport education trainees before and 1 and 4 days after exercise. To visualize muscle injury, MRI of the loaded thigh was performed before and 4 days after the eccentric exercise. All participants recorded an increase ( P ? 0.05) in creatine kinase after exercise. In five participants, T2 signal intensity was unchanged post-exercise compared with pre-exercise and MHC plasma concentration was normal; however, they showed an increase ( P ? 0.05) in creatine kinase after exercise. For the remaining five participants, there was an increase in T2 signal intensity of the loaded vastus intermedius and vastus lateralis. These changes in MRI were accompanied by an increase in MHC plasma concentration ( P ? 0.01) as well as an increase in creatine kinase ( P ? 0.01). We suggest that changes in MRI T2 signal intensity after muscle damage induced by eccentric exercise are closely related to damage to structurally bound contractile filaments of some muscle fibres. Additionally, MHC plasma release indicates that this damage affects not only fast-twitch fibres but also some slow-twitch fibres. 相似文献
20.
ABSTRACT The purpose of this scoping review was to provide an overview of studies concerning the mental health (MH) of elite athletes and to provide a methodological, conceptual, and applied overview of factors affecting elite athletes’ MH. A total of nine reviews and 43 empirical studies were evaluated and are reported in three sections: sample characteristics, research design, and factors affecting elite athletes’ MH. These factors were grouped into risk and protective factors and divided into a personal and sport-environmental domain. The studies used quantitative (84%), qualitative (11%), and mixed-method (5%) designs and examined a wide range of sports in different countries. Our review shows that researchers have predominantly examined the prevalence of athletes’ mental ill-health (e.g. depression) and the related factors compromising MH. Potential protective factors such as the feeling of autonomy, positive relations in sport and private life, and adequate recovery were highlighted in the qualitative studies. The discussion appraises the findings through a critical lens, focuses on the current state of the research area and the MH definition, limitations, suggested practical implications (e.g. to provide MH literacy to both athletes and coaches), and future research directions (e.g. examining environments that foster elite athletes’ MH). 相似文献