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1.
Thigh muscle volume is a useful determinant of functional fitness. However, anthropometric prediction of muscle content is influenced by the variability of adipose tissue accumulation. The aims of this study were to predict thigh muscle and adipose tissue volumes from anthropometry and to assess the validity of the method by examining the various components of the measurements and the assumptions involved. The 19 participants (9 men, 10 women; age 23-49 years) varied in adiposity. They all underwent magnetic resonance imaging (MRI) of the upper leg and the eight men and two women with the lowest adiposity underwent detailed anthropometry involving girths and skinfolds. Using MRI as the reference method, muscle volume was predicted from anthropometry using a circular concentric model, and the assumptions inherent in the method were tested further using the MRI data alone. Muscle volume was best predicted by anthropometry in the 10 leanest participants using a five-slice truncated cone model that overestimated the mean MRI value by 30% ( R 2 = 0.95; standard error of estimate = 288 cm 3 ; P ? 0.001). A single skinfold plus girth measurement at the mid-thigh almost matched its predictive ability, but with an increased bias. Measurements of leg circumference by means of the two techniques agreed well. The assumption of a circular cross-section was valid. In contrast, the agreement between skinfold thickness measured by caliper and superficial adipose tissue thickness by MRI was poor, contributing to the scatter of fat and lean area comparisons. An anterior skinfold thickness measurement underestimated the area of superficial adipose tissue at that level, particularly at the most proximal and distal sites. Although these limitations increase the uncertainties of muscle volume determination by anthropometry, they do not prevent its valid prediction in leaner individuals. The prediction of superficial adipose tissue was poorer. 相似文献
2.
The interest in skinfolds, given the easy accessibility of the subcutaneous layer and its non-invasive nature, has led to a proliferation of 'skinfold' applications and formulae. To obtain data to investigate body composition methods, particularly the use of skinfolds, two separate cadaver dissection studies were undertaken, allowing for the analysis of data from 32 cadavers with more than 2500 data per cadaver. In addition, 40 elderly 'living' subjects of the same age range were compared with the cadaver population and no significant macro-morphological differences were found. The available data have clearly demonstrated that skinfold compressibility is by no means constant. Adipose tissue patterning by assessment of skinfold thickness using calipers and incision confirms significant sex differences but emphasizes the neglected importance of skin thickness. It appears that the best adipose tissue predictors are different from those used in general. Also the problem of estimating body fat content by skinfold is compounded by the fact that two identical thicknesses of adipose tissue may contain significantly different concentrations of fat. Skinfolds are significantly related to external (subcutaneous) adipose tissue. However, the relation to internal tissue is less evident and the relation with intramuscular adiposity is unknown. 相似文献
3.
The ability of bioelectrical impedance analysis and anthropometry to predict fat mass and fat-free mass was compared in a sample of 82 male athletes from a wide variety of sports, using dual-energy X-ray absorptiometry (DXA) as the reference method. The percent fat measured by DXA was 10.9 - 4.9% (mean - s ), and fat mass was predicted with a standard error of the estimate of 1.7 kg for skinfolds and 2.8 kg for bioelectrical impedance analysis (P?0.001). Fat-free mass was predicted with a standard error of the estimate of 1.7 kg for anthropometry and 2.6 kg for bioelectrical impedance analysis (P?0.001). Regression of various individual skinfolds and summed skinfolds, to examine the eff ect of skinfold selection combinations by stepwise regression, produced an optimal fat mass prediction using the thigh and abdominal skinfold sites, and an optimal fat-free mass prediction using the thigh, abdominal and supra-ilium sites. These results suggest that anthropometry off ers a better way of assessing body composition in athletes than bioelectrical impedance analysis. Applying the derived equations to a separate sample of 24 athletes predicted fat and fat-free mass with a total error of 2.3 kg (2.9%) and 2.2 kg (2.7%), respectively. Combining the samples introduced more heterogeneity into the sample (n=106), and the optimal prediction of fat mass used six skinfolds in producing a similar standard error of the estimate (1.7 kg), although this explained a further 4% of the variation in DXA-derived fat. Fat-free mass was predicted best from four skinfolds, although the standard error of the estimate and coefficient of determination were unchanged. 相似文献
4.
The ability of bioelectrical impedance analysis and anthropometry to predict fat mass and fat-free mass was compared in a sample of 82 male athletes from a wide variety of sports, using dual-energy X-ray absorptiometry (DXA) as the reference method. The percent fat measured by DXA was 10.9+/-4.9% (mean +/- s), and fat mass was predicted with a standard error of the estimate of 1.7 kg for skinfolds and 2.8 kg for bioelectrical impedance analysis (P < 0.001). Fat-free mass was predicted with a standard error of the estimate of 1.7 kg for anthropometry and 2.6 kg for bioelectrical impedance analysis (P < 0.001). Regression of various individual skinfolds and summed skinfolds, to examine the effect of skinfold selection combinations by stepwise regression, produced an optimal fat mass prediction using the thigh and abdominal skinfold sites, and an optimal fat-free mass prediction using the thigh, abdominal and supra-ilium sites. These results suggest that anthropometry offers a better way of assessing body composition in athletes than bioelectrical impedance analysis. Applying the derived equations to a separate sample of 24 athletes predicted fat and fat-free mass with a total error of 2.3 kg (2.9%) and 2.2 kg (2.7%), respectively. Combining the samples introduced more heterogeneity into the sample (n = 106), and the optimal prediction of fat mass used six skinfolds in producing a similar standard error of the estimate (1.7 kg), although this explained a further 4% of the variation in DXA-derived fat. Fat-free mass was predicted best from four skinfolds, although the standard error of the estimate and coefficient of determination were unchanged. 相似文献
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6.
Tim J. Gabbett 《Journal of sports sciences》2013,31(12):1273-1280
Abstract This study compared the physiological and anthropometric characteristics of specific playing positions and positional playing groups in sub-elite rugby league players. Altogether, 415 sub-elite rugby league players underwent measurements of standard anthropometry (body mass, height, sum of four skinfolds), muscular power (vertical jump), speed (10-m, 20-m, and 40-m sprint), agility (“L” run), and estimated maximal aerobic power (multi-stage fitness test). Props were significantly heavier and had a greater skinfold thickness than all other playing positions. Centres, fullbacks, and hookers were faster than props over 40 m. When the data were analysed according to positional commonality, props were taller, heavier, had a greater skinfold thickness, were less agile, and were slower over 10 m than all other positional groups. The hookers/halves and outside backs positional groups were significantly faster over 40 m than the backrowers and props positional groups. In addition, the hookers/halves and outside backs positional groups had significantly greater estimated maximal aerobic power than the props positional group. The results of this study demonstrate that few physiological and anthropometric differences exist among individual playing positions in sub-elite rugby league players, although props are taller, heavier, have greater skinfold thickness, slower 10-m and 40-m speed, less agility, and lower estimated maximal aerobic power than other positional groups. These findings provide normative data for sub-elite rugby league players competing in specific individual positions and positional playing groups. 相似文献
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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.
Gabbett TJ 《Journal of sports sciences》2006,24(12):1273-1280
This study compared the physiological and anthropometric characteristics of specific playing positions and positional playing groups in sub-elite rugby league players. Altogether, 415 sub-elite rugby league players underwent measurements of standard anthropometry (body mass, height, sum of four skinfolds), muscular power (vertical jump), speed (10-m, 20-m, and 40-m sprint), agility ("L" run), and estimated maximal aerobic power (multi-stage fitness test). Props were significantly heavier and had a greater skinfold thickness than all other playing positions. Centres, fullbacks, and hookers were faster than props over 40 m. When the data were analysed according to positional commonality, props were taller, heavier, had a greater skinfold thickness, were less agile, and were slower over 10 m than all other positional groups. The hookers/halves and outside backs positional groups were significantly faster over 40 m than the backrowers and props positional groups. In addition, the hookers/halves and outside backs positional groups had significantly greater estimated maximal aerobic power than the props positional group. The results of this study demonstrate that few physiological and anthropometric differences exist among individual playing positions in sub-elite rugby league players, although props are taller, heavier, have greater skinfold thickness, slower 10-m and 40-m speed, less agility, and lower estimated maximal aerobic power than other positional groups. These findings provide normative data for sub-elite rugby league players competing in specific individual positions and positional playing groups. 相似文献
10.
对评价大学生身体成分方法的研究 总被引：2，自引：0，他引：2
为研究在校大学生身体成分测量的最佳方法,采用皮褶法、生物电阻抗法(BAI)、身体质量指数(BMI)、腰臀比(WHR)和身高标准体重法,分别对随机抽取的220名大学生进行身体成分测试,并进行相关分析。结果发现:1.BAI、皮褶法、BMI和WHR可用来测量和评价大学生的身体成分,但其准确性依次是BAI>皮褶法>BMI>WHR;2.《标准》中身高标准体重不能客观有效地评价身体成分,故建议选用体脂百分比。 相似文献
11.
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
12.
目的:研究耐力训练对大鼠FTO基因表达的影响以及与摄食量的关系。方法:以SD大鼠为研究对象,将大鼠分为对照组(C组)和运动训练组(E组),以12周无负重游泳为运动手段,测定肝脏、骨骼肌、脂肪组织和下丘脑组织中FTO基因mRNA表达、大鼠体重、肾周与附睾周围脂肪重量及脂肪重量与体重百分比、大鼠每天摄食量。结果:FTO基因mRAN在骨骼肌、脂肪组织和下丘脑中表达均显著高于肝脏组织,下丘脑显著高于骨骼肌和脂肪组织,脂肪组织与骨骼肌未见显著性差异,耐力训练对肝脏、骨骼肌和脂肪组织中FTO基因mRNA表达未见显著性影响,而脑组织表达显著升高;大鼠体重在不同的对应时间点,运动训练组与对照组未见显著性差异;大鼠摄食量在不同对应时间点,运动训练组显著高于对照组;肾周及附睾周围脂肪组织重量及脂肪重与体重百分比运动训练组显著低于对照组。结论:耐力训练可以提高下丘脑中FTO基因表达,从而刺激大鼠提高摄食量,而运动能量的消耗抵消了因摄食增加引起的体重增加。 相似文献
13.
Blood flow restriction training technique can be affected by several factors resulting in changes in responses to training; therefore it is necessary to investigate and reveal detailed information about this novel training technique. Participants had their thigh size, thickness of subcutaneous fat, and regional bone free muscle mass measured prior to testing. A Near-Infrared Spectrometer was used to measure tissue oxygenation and a cardiovascular profiling system was utilised to measure stroke volume and heart rate. Initial restrictive pressure of 30, 50, and 70 mmHg were set in random order on three separate days, and then six target pressures were sequentially applied. Tissue oxygenation decreased significantly as both initial restrictive pressure and target pressures increased, but the magnitude of decreases was stronger with higher initial restrictive pressure. There were significant negative correlations between tissue oxygenation and leg lean body mass, total lean body mass, and thigh circumference when initial restrictive pressure was set at 30 mmHg. The findings indicated that changes in initial restrictive pressure affected the amount of venous return verified by the decreases in tissue oxygenation and stroke volume. In addition, thigh composition and size had a significant impact on the effects of initial restrictive pressure. 相似文献
14.
《European Journal of Sport Science》2013,13(4):378-385
Abstract Adiponectin mRNA and plasma concentrations were reduced in obesity. Exercise training may reduce the adipose tissue (AT), although it is not well known, whether exercise – induced change in AT, increases adiponectin mRNA expression and plasma concentrations or not. Therefore, the purpose of this study was to examine the effects of short-term lifestyle activity modification (LAM) on adiponectin mRNA and plasma concentrations. Sixteen obese and overweight middle-aged men (age, 35–50 years) with type 2 diabetes participated in this study. The subjects were randomly assigned to LAM group (n=8) or control group (n=8). The subjects in LAM group walked two miles in 30 min on a treadmill on 4 days per week for 12 weeks according to the guidelines of the Centers for Disease Control and Prevention and American College of Sports Medicine. The results showed that body mass, body mass index, central visceral adipose tissue and subcutaneous adipose tissue volume and hip and thigh subcutaneous adipose tissue (hip and thigh SAT) volume were decreased in the LAM group compared to the control group (P<0.05). Adiponectin mRNA in abdominal and gluteal subcutaneous AT were increased significantly in the LAM group compared to the control group (P<0.05), while plasma adiponectin concentrations, hs-CRP and insulin resistance did not change significantly. In conclusion, adiponectin mRNA levels increase after 12 weeks of LAM; however, plasma adiponectin levels were not affected by this protocol in obese and overweight middle-aged men with type 2 diabetes. 相似文献
15.
Popadic Gacesa J Dragnic NR Prvulovic NM Barak OF Grujic N 《Journal of sports sciences》2011,29(6):635-641
The aim of this study was to determine whether triceps brachii muscle volume can be adequately estimated from a single anatomical cross-sectional area (ACSA) and can the same model be used for prediction after training. Thirty-five healthy male non-athletes (age 21.6 ± 2.5 years, body mass index 24.8 ± 3.5 kg · m(-2)) volunteered for this study. The volumes of the upper arm extensors were calculated from magnetic resonance imaging (MRI) sequence scans and regression models were developed, which were used to predict muscle volumes from single MRI cross-sectional scans taken at different points along the humerus length. The same procedure was repeated after 12 weeks of maximal resistance training of the elbow extensors. Correlation coefficients were calculated for Model A with CSA(max), humerus length (HL), and body mass index (r = 0.919), a model with CSA(50%) and HL (r = 0.922), and a model with CSA(60%) and HL (r = 0.920) (P < 0.001). The standard error of estimate for Model A, Model CSA(50%), and Model CSA(60%) was 8.0%, 7.7%, and 7.8% respectively. Thesame prediction formula can be used for the left arm (r = 0.904). If a single ACSA is used for triceps brachii volume prediction, the best fit is with Model CSA(60%) and HL, both before and after training (r = 0.941). By introducing humerus length into the calculation, we simplify the procedure for volume measurement, since it can be obtained during MRI scanning. 相似文献
16.
Alan M. Nevill Edward M. Winter Steve Ingham Adam Watts Georgios S. Metsios Arthur D. Stewart 《Journal of sports sciences》2013,31(9):1009-1016
Abstract The aim of the present study was to identify when body mass index (BMI) is unlikely to be a valid measure of adiposity in athletic populations and to propose a simple adjustment that will allow the BMI of athletes to reflect the adiposity normally associated with non-athletic populations. Using data from three previously published studies containing 236 athletes from seven sports and 293 age-matched controls, the association between adiposity (sum of 4 skinfold thicknesses, in millimetres) and BMI was explored using correlation, linear regression, and analysis of covariance (ANCOVA). As anticipated, there were strong positive correlations (r = 0.83 for both men and women) and slope parameters between adiposity and BMI in age-matched controls from Study 1 (all P < 0.001). The standard of sport participation reduced these associations. Of the correlations and linear-regression slope parameters between adiposity and BMI in the sports from Studies 2 and 3, although still positive in most groups, less than half of the correlations and slope parameters were statistically significant. When data from the three studies were combined, the ANCOVA identified that the BMI slope parameter of controls (5.81 mm · (kg · m?2)?1) was greater than the BMI slope parameter for sports (2.62 mm · (kg · m?2)?1) and middle-distance runners (0.94 mm · (kg · m?2)?1) (P < 0.001). Based on these contrasting associations, we calculated how the BMI of athletes can be adjusted to reflect the same adiposity associated with age-matched controls. This simple adjustment allows the BMI of athletes and non-athletes to be used with greater confidence when investigating the effect of BMI as a risk factor in epidemiological research. 相似文献
17.
踝关节跖屈肌肌肉肌腱形态及收缩效应的相关研究 总被引：2，自引：0，他引：2
应用螺旋CT及体视学研究方法对普通大学生踝关节跖屈肌肌肉肌腱形态进行了较全面的测量分析,同时采用六维测力平台结合表面肌电测量仪测定最大跖屈力,探讨跖屈肌肌肉肌腱形态与收缩效应之间的关系。结果表明:①小腿跖屈肌横断面积、体积和小腿围度与肌肉力量之间存在密切的关系;②小腿长、腓肠肌长、比腓肠肌肌腱长与肌力有着明显的相关;比目鱼肌长只与提踵肌力有关;③跟腱长、比跟腱长和腓肠肌肌腱长与肌力之间不具相关性。 相似文献
18.
Abstract Changes were observed in the thickness of a subcutaneous fat layer as a result of exercising an underlying unilateral muscle over a period of time using the subcutaneous fat layer over the inactive contralateral muscle as a control. The observations were made on 15 male subjects who participated in a ten-week weight-training program which involved the triceps of the dominant arm. A Harpenden skinfold caliper was used to estimate the thickness of the subcutaneous fat layers. The findings did not support the postulate that subcutaneous fat is reduced in localities where muscles are active and in proportion to their activity. 相似文献
19.
Effects of rest interval during high-repetition resistance training on strength, aerobic fitness, and repeated-sprint ability 总被引：1，自引：0，他引：1
The effect of altering the rest period on adaptations to high-repetition resistance training is not well known. Eighteen active females were matched according to leg strength and repeated-sprint ability and randomly allocated to one of two groups. One group performed resistance training with 20-s rest intervals between sets, while the other group employed 80-s rest intervals between sets. Both groups performed the same total training volume and load. Each group trained 3 days a week for 5 weeks [15- to 20-repetition maximum (RM), 2 - 5 sets]. Repeated-sprint ability (5x6-s maximal cycle sprints), 3-RM leg press strength, and anthropometry were determined before and after each training programme. There was a greater improvement in repeated-sprint ability after training with 20-s rest intervals (12.5%) than after training with 80-s rest intervals (5.4%) (P = 0.030). In contrast, there were greater improvements in strength after training with 80-s rest intervals (45.9%) than after training with 20-s rest intervals (19.6%) (P = 0.010). There were no changes in anthropometry for either group following training. These results suggest that when training volume and load are matched, despite a smaller increase in strength, 5 weeks of training with short rest periods results in greater improvements in repeated-sprint ability than the same training with long rest periods. 相似文献
20.
《European Journal of Sport Science》2013,13(5):287-294
Abstract Information on the prediction of adult relative fat mass (percent body fat,%BF) using measures from pre-pubertal ages and early childhood is scarce. In the present longitudinal study, we assess the development of different anthropometric indicators of percent body fat during childhood, adolescence, and adulthood in 37½-year-old females stratified for low and high percent body fat. Consequently, we study the predictability of percent body fat based on simple anthropometric measurements during childhood and adolescence. Anthropometric data from the Belgian longitudinal experimental growth study “LEGS” were used. Beginning in 1969, five yearly cohorts of about 100 individuals each (mean age 6 years) were recruited in public kindergartens. Of the original 515 participants (260 males, 255 females) that were measured annually from age 6 to 18 years, 59 males and 60 females agreed to participate in a follow-up study in 2004. During the follow-up measurements, the participants were invited for a body-composition assessment by bioelectrical impedance analysis (BIA). We stratified the participants into low (%BF-BIA < 35%) and high (%BF-BIA≥35%) relative fat mass samples. Pearson correlations were calculated and used as tracking coefficients. Multiple stepwise linear regression was applied with anthropometric variables at each age separately as predictors for adult percent body fat, expressed as%BF-BIA, %BF-Segal, and %BF-D&W (Durnin & Womersley, 1974). The results indicate that a single skinfold thickness during adolescence is a better predictor for adult percent body fat than adolescent body mass index. Additionally, our results suggest that this holds during childhood as early as from age 8 onwards. The use of single skinfold measurements as predictors for adult adiposity and obesity is supported by other arguments, including: (1) body mass index as a proxy for overweight does not discriminate between fat mass and fat-free mass, and (2) an excess of adipose tissue is more strongly associated with morbidity than the body mass index. 相似文献