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1.
Abstract

The relative importance of body size, body composition, cardiovascular-respiratory capacity, and running speed in determining individual differences in performance on 600-yd run and mile run tests was investigated using data on 196 children, ages 7 to 12 years. A multivariate, multistage path model was developed in which height, % fat, [Vdot]O2 max (ml/kg FFW · min) and the 50-yd dash time were postulated as determinants of individual differences on the two distance-running tests. These four independent variables accounted for 71% and 66% of the variance in the 600-yd run and mile run, respectively. All four independent variables had significant associations with the two distance runs when the influence of the other independent variables was taken into account. The 50-yd dash time and % fat were found to be the most important determinants of both distance runs. It was concluded that determinants of the 600-yd run and mile run in elementary-school-age children are complex and that individual differences on these tests reflect a number of attributes in addition to cardiovascular-respiratory capacity.  相似文献   

2.
Abstract

The purpose of this paper was to understand which differences long-term swimming training can cause on trunk mechanics during breathing and how these differences are related to the years of swimming training. The variations and coordination among trunk compartments were considered as target movement patterns. Video-based plethysmography was utilised for data acquisition and pre-processing. A group of swimmers, who followed a long-term intensive swimming training previously to this study, was compared with a non-swimmer control group. The participants of both groups performed quiet breathing and vital capacity tests. From the compartmental volumes associated with each breathing curves, the relative amplitude and cross-correlation among these volumetric time-varying signals were calculated, in order to analyse the relative partial volume variation and the coordination among trunk compartments involved in respiration. The results of a Mixed-ANOVA test (P ≤ 0.05) revealed higher coefficient of variation (P < 0.001) and correlations among trunk compartments in the swimmers group when vital capacity was performed. Significant linear regression was found between the years of swim training and the coefficients of variation and correlation. The results suggest that after long periods of intensive swim training, athletes might develop specific breathing patterns featuring higher volume variations in the abdominal region and more coordination among compartments involved in forced respiratory tasks such as vital capacity.  相似文献   

3.
运动减肥中运动强度确定依据的实验研究   总被引：9，自引：0，他引：9  
采用实验法,分别测定体脂百分比低、中、高3组受试者在递增运动负荷中的有氧能力指标、呼吸商等气体代谢指标以及无氧运动能力指标,研究体脂百分比与其之间的关系。结果发现:体脂百分比与有氧、无氧能力各指标间呈显著的负相关;在样本整体运动能力均处于低水平的状况下,高体脂百分比组有氧和无氧运动能力均较差;在递增运动负荷中,高体脂百分比组的呼吸商上升幅度较大,在接近乳酸阈值附近呼吸商值偏高。说明高体脂成分是机体运动能力的限制因素;对于运动水平较低的个体,在较低负荷下结合呼吸商情况,确定运动减肥强度具有重要意义。提示:肥胖程度高的个体,其乳酸阈值小,相应的乳酸阈强度低,在运动减肥中应采取相对较小的运动强度。  相似文献   

4.
Abstract

Fatigue curves for the forearm muscles, doing maximal static and dynamic work, were obtained under control conditions and under conditions of hyperaemia. The hyperaemia was evoked by subjecting the muscles of the forearm for a specific length of time to circulatory occlusion with a blood pressure cuff and then suddenly releasing the cuff pressure. The maximal increase in forearm volume, resulting from the postocclusion hyperaemia, followed a mathematical curve when it was expressed as a function of the occlusion time. A significant decrement in work capacity was found immediately after ten minutes of occlusion. This short-time negative influence did not affect the total output.  相似文献   

5.
Abstract

Relative isometric endurance tests of 50, 60, 70, and 80 percent weight loads were used to evaluate the muscular endurance of three groups of male college students. The 47 students were grouped according to level of athletic achievement. Analysis of variance models failed to detect any differences between the endurance of the three groups. Consideration was given to the use of relative endurance tests for evaluating levels of motivation.  相似文献   

6.
文章通过对山西省武术管理中心16名青少年武术套路运动员进行了无氧功测试、血乳酸测试,测试所获数据采用秩和检验进行组间均数比较,并对wingate结果和血乳酸结果进行相关性检验,得出结论：（1）青少年武术套路运动员的无氧能力并不是影响成绩的主要因素。（2）青少年武术套路运动员的无氧能力相比体能占主导的无氧运动而言较差。（3）wingate测试的各项指标采用其体重相对值更能反映运动员之间无氧能力的差别。（4）运动后7分钟的血乳酸水平可以反应青少年武术套路运动员的无氧能力水平。  相似文献   

7.

We tested the hypothesis that quiet eye, the final fixation before the initiation of a movement in aiming tasks, is used to scale the movement's parameters. Two groups of 12 participants (N = 24) threw darts to targets in the horizontal and vertical axes under conditions of higher (random) or lower (blocked) target variability. Supporting our predictions, random practice and target changes in the vertical axis led to longer quiet eye duration than did blocked practice and target changes in the horizontal axis. Our data suggest that quiet eye is not simply a mediating factor in accuracy, but is responsive to the task's programming demands, being influenced by the necessity to reparameterize the movement from one trial to the next.  相似文献   

8.
Abstract

Thirty-three college men doing the toe-touch test were used as subjects to ascertain the relative contribution of the back and hamstring muscles to hip joint flexibility. The subjects, performing six tests over a 5-week period, were photographed during each of their tests. Anthropometric measurements were taken prior to testing to determine if there was any relationship to flexibility. Making use of concentric circles and marking reference points on the subject prior to testing, it was possible to ascertain the curvature of the back, the angle of straight back flexibility, and the angle of bent back flexibility.

Results indicate that the extensibility of the hamstring muscles appeared to be one of the main contributing factors to hip joint flexion, and since the warm-up did not affect the flexibility of the back, one might conclude that the back made no increased contribution to hip joint flexion, as measured in this study. There was no significant relationship to the angle of bent back flexibility.  相似文献   

9.
Abstract

The relationship between maximal oxygen intake (Max V02) and the capacity for endurance performance was investigated in a sample of 30 male university students. Each subject performed two work capacity tests on a bicycle ergometer from which continuous, minute-by-minute oxygen intake values, the amount of work performed (kilopond-meters), and the length of the ride (seconds) were obtained. In addition, lean body weight and percent body fat were measured in order to ascertain their importance in the above relationship. The results indicate a fairly high correlation (r = .84) between Max VO2 (liters/min.) and endurance capacity, but this relationship was reduced considerably when Max VO2 was expressed relative to body weight (r=.37) and lean body weight (r = .18). However, when the influence of body weight and lean body weight were held statistically constant, the correlations of endurance capacity with Max VO2 (ml/kg per min.) and Max VO2 (ml/LBW/ min.) increased to r=.78 and r = .64 respectively. Thus, it was concluded that there is a substantial relationship between endurance capacity and Max V02 which is essentially independent of the form in which Max VO2 is reported providing the influence of body weight and lean body weight on both variables are taken into account.  相似文献   

10.
ABSTRACT

As the world is witnessing the epidemic of coronavirus disease 2019, emerging genetics and clinical pieces of evidence suggest a similar immunopathology to those of severe acute respiratory syndrome and Middle East respiratory syndrome. Staying at home to prevent the spread of the virus and consequently being largely inactive is associated with unintended consequences. These can actually enhance the infection risk and exacerbate poor health conditions including impaired immune function. Physical activity is a feasible way of improving health, particularly physical and mental health in a time of social isolation. However, people with certain health conditions in these circumstances may need a special physical activity programme in addition to any exercise they may already be performing via online programmes. This review aims to provide practical guidelines during the COVID-19 quarantine period. We suggest performing aerobic, resistance training, respiratory muscle training and yoga in the healthy, and in those with upper respiratory tract illness, patients with lower respiratory tract illness should be restricted to respiratory muscle training and yoga. In addition, vitamins D and C, omega-3 fatty acids, and regular consumption of fruit and vegetables might be considered as nutritional aids to support the immune system in those affected by COVID-19.  相似文献   

11.
Abstract

Thirty-six male college students were measured in six cardiovascular factors as recorded by the Cameron Heartometer. Seventeen of these subjects were smokers and 19 were non-smokers. The purpose of this investigation was to find what residual, as opposed to acute, effects, smoking has on young men. Each subject in both groups was measured in six cardiovascular factors, nine times successively, during his testing period. The smokers abstained from smoking on the day of testing.

The residual effects of smoking in young men, if there be any, cannot be demonstrated in a statistically significant manner in certain cardiovascular factor measurements in the quiet state.  相似文献   

12.
不同运动项目对老年人身体形态和机能的锻炼效果研究   总被引：6，自引：0，他引：6  
采用不同的运动项目实验后发现,老年人腰臀比指数明显下降,肺活量指数比运动前有增高的趋势,安静心率降低,血压偏高的受试者实验后收缩压和舒张压均恢复到正常范围,表明科学健身运动对增强骨骼肌,改善呼吸和循环系统的生理功能有明显效果。  相似文献   

13.
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14.
Abstract

This article analyses the conditions influencing volunteering in sports clubs. It focuses not only on individual characteristics of volunteers but also on the corresponding structural conditions of sports clubs. It proposes a model of voluntary work in sports clubs based on economic behaviour theory. The influences of both the individual and context levels on the decision to engage in voluntary work are estimated in different multilevel models. Results of these multilevel analyses indicate that volunteering is not just an outcome of individual characteristics such as lower workloads, higher income, children belonging to the sports club, longer club memberships, or a strong commitment to the club. It is also influenced by club-specific structural conditions; volunteering is more probable in rural sports clubs whereas growth-oriented goals in clubs have a destabilising effect.  相似文献   

15.
Abstract

In this study, we investigated the effect of 1- and 3-week tapering periods on concentrations of plasma testosterone (T), cortisol (C), T/C ratio, mood state, and performance in elite male cyclists. After 8 weeks of progressive training, cyclists were randomly assigned to a control group (n=12) who continued performing intense training for a further 3 weeks, or a taper group (n=12) who continued with a 50% reduction in training volume. Blood testosterone and cortisol concentrations were assayed and the T/C ratio calculated from analysis obtained via standard ELISA. Mood state was determined using the Profile of Mood States (POMS) questionnaire. All data were collected immediately after a 40-km time-trial performed before, during, and after the 8-week training protocol and after the 1- and 3-week tapering/training periods. In the taper group, 40-km time-trial time decreased significantly (P<0.01) and equally for both the 1- and 3-week taper periods relative to the control group. There were significant elevations in T/C ratio (P<0.001) and reductions in cortisol concentrations and POMS scores in the taper group relative to the control groups at the end of both the 1- and 3-week tapering periods. Hence, taper periods are effective in improving performance and mood state and elevating the blood T/C ratio.  相似文献   

16.
Abstract

Thai ginseng, Kaempferia parviflora, is widely believed among the Mong hill tribe to reduce perceived effort and improve physical work capacity. Kaempferia parviflora is consumed before their daily work. Therefore, we conducted an acute study on the effects of K. parviflora on repeated bouts of sprint exercise and on endurance exercise time to exhaustion. Two studies were conducted in college males using a randomized, double-blind, crossover design. Ninety minutes after consumption of K. parviflora or a starch placebo, participants in study 1 (n = 19) completed three consecutive maximum 30-s sprint cycling Wingate tests, separated by 3 min recovery, while participants in study 2 (n = 16) performed submaximal cycling exercise to exhaustion. Peak and mean power output decreased with successive Wingate tests, while percent fatigue and blood lactate concentration increased after the third Wingate test (P < 0.05). There were no detectable differences in any measures with or without K. parviflora. There was also no effect of K. parviflora on time to exhaustion, rating of perceived exertion or heart rate during submaximal exercise. Our results indicate that acute ingestion of K. parviflora failed to improve exercise performance during repeated sprint exercise or submaximal exercise to exhaustion. However, chronic effects or actions in other populations cannot be excluded.  相似文献   

17.
运用实验测试法测定北京市40-59岁普食者与素食者安静时的身体形态指标、BMI、肺活量、心率、血压等指标,并对其进行比较分析。结论:安静时普食者与素食者的身高、BMI、腰臀比之间有显著性差异;普食者与素食者男性在安静状态下心率有显著性差异,素食者均比普食者低;普食者与素食者女性的台阶指数间具有显著性差异,且素食者比普食者的低;普食者与素食者在握力指标上存在显著性差异,且普食者比素食者大。建议:加强普食者与素食者在营养和卫生保健知识方面的普及;加大他们对科学健身的认识及合理膳食的搭配。  相似文献   

18.
促肝细胞生长因子是从胎肝中提取,且内含肝细胞生长因子、骨髓刺激因子等多种生物活性的多肽物质。动物实验表明：它能明显提高Ｈｂ值、空腹血糖值、安静时ＩＣＤ活性、安静和应激后的氧耗率和抗疲劳能力;能降低安静时ＣＫ活性,提高其应激后ＣＫ活性。耐缺氧能力提高不明显。  相似文献   

19.
Abstract

Males (N = 7), ages 23–45, were tested on a maximum and two submaximum performance tests to determine the effects of different intensities of exercise on intraocular pressure. Intraocular pressure, blood pH, and blood lactate concentration were measured at rest, the midpoint of the submaximum tests, the end of exercise, and during the first 10 min of recovery. A two-way ANOVA was employed to determine if any significant differences existed between means due to the exercise or the intensity. The results of this study indicate that the intraocular pressure decreases during exercise and the first few minutes of recovery. However, the intensity of the exercise was not related to the amount of decrease in intraocular pressure. The decrease in pressure was associated with a decrease in blood pH and an increase in blood lactate concentration.  相似文献   

20.
Abstract

Three increasingly intense levels of endurance training were evaluated in terms of their capacity to change efficiency. The intensity of the training was controlled by the heart rate achieved during each training bout. The submaximal character of the testing bouts was established by means of blood lactate monitoring. In addition to the investigation of efficiency changes, heart rate, respiratory rate, and respiratory volume were involved in analysis. Parametric statistical procedures characterized efficiency as most useful in predicting changes resulting from training. Correlation matrices revealed that heart rate could also be used with a good degree of confidence to predict the extent of alterations brought about by training of this sort. The rate of increase in chronic change due to training was not related directly to the increments of training intensity since no changes occurred at or below a 120 heart rate.  相似文献   

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