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1.
本文意在探讨以80%Vo_(2max)运动至力竭后,女子血浆雌二醇(E_2)、醛固酮(A)和促甲状腺素(TSH)的变化及其性别差异。本文对55名受试者(男28名,女27名)进行了渐增负荷实验(测定、Vo_(2max)和无氧阈)与固定负荷实验(测定运动持续时间及激素变化)。结果显示:女子Vo_(2max)明显低于男子(p<0.05),但以80%Vo_(2max)运动至力竭,女子运动持续时间较长(p<0.05),其血浆E_2、A和TSH均明显增高(p<0.05),男子则变化不明显(p>0.05)。可以说明:以相同强度运动时,女子运动持续时间较长,E_2、A与TSH对运动的反应较男子更为敏感。  相似文献   

2.
最大耗氧量(Vo_2max)是反映人体有氧活动能力的重要指标,可应用于儿童青少年动态机能发育水平的研究。通过极量运动试验及气体分析仪直接测定所得Vo_2max相当精确,但直接测定法需要昂贵的仪器设备和一定的技术条件,费时费力,只能在有条件的实验室内进行。更由于测定时受试者的运动要达到筋疲力竭的程度,有一定危险性,故这一方法不适宜于在大数量人群中普遍使用。因此,在国外广泛应用比  相似文献   

3.
13岁中学生的最大有氧活动能力   总被引:2,自引:0,他引:2  
最大有氧活动能力是指机体在极量运动状态下吸收和利用氧的能力,说明这种能力的指标为最大耗(吸)氧量(Maximal oxygen consumpfion;Maximaloxygen intake:Vo_2max)。在国外,Vo_2max已广泛应用于运动员选材、运动能力的判断、劳动力鉴定、临床心肺功能检查及儿童生长发育评价诸方面。Vo_2max的大小与心血管系统、呼吸系统功能、血液携带及输送氧的能力及组织吸收利用氧的能力有关,因而它能综合反映儿童体格、机能的发育状况,是判断儿童发育水平及不同环境因素对儿童体质影响的比较理想的动态机能指标。国外已陆续测定了各年龄阶段儿童和成人的最大有氧能力,建立了比较完整的资料。我国关于一般儿童Vo_2max的研究刚刚开始。  相似文献   

4.
在严重缺铁时,通过踏车运动实验,发现两种运动体能减弱。即Vo_2max(最大摄氧量)和耐力减弱。其机制可能是:1.由于贫血氧向组织解离受限,2.由于肌肉线粒体中含铁氧化酶的活力减弱而导致氧化代谢下降。用交换输血法对老鼠的Hb(血红蛋白)浓度研究表明,在短暂而剧烈的运动中,Vo_2max和最大运动负荷常被用来做为测定贫血程度的标志;  相似文献   

5.
整体有氧耐力主要依赖于机体的有氧代谢能力,在运动生理和运动医学上用人体的最大摄氧量(Vo_2max)和乳酸性阈值(Vo_2LA)或无氧代谢阈(Vo_2AT)作为其最可靠的评价指标.但这些指标在运用上需要高级精密的仪器和熟练的操作技术,并且测试方法较复杂.  相似文献   

6.
在逐增负荷的运动中所测定的单位体重最大耗氧量(Vo_2max/kgb),最大心率(maxHR)和最大血乳酸含量有较大的个体差异。本文的目的是确定这三项指标的家族关系。38个法(国)一加(拿大)血统家庭的双亲及其子女参加了“勃克”改良跑台运动。在运动中,测出受试者的Vo_2max/kgb和maxHR。运动后二分钟取血样,以测乳酸最大浓度。不  相似文献   

7.
女子赛艇运动员在模拟比赛中心肺功能的动态变化   总被引:3,自引:0,他引:3  
本文以女子赛艇运动员为研究对象,观察了她们在模拟比赛过程中VE、Vo_2、HR、RQ、EQ—O_2、Vo_2/HR等指标的变化情况.本研究的模拟器械选用最先进的计算机控制的赛艇测功系统,较以往模拟手段更为符合实际情况.根据观察结果,本文对以上指标的变化意义作了讨论.还报告了一组省级女子赛艇运动员的Vo_2max、AT.  相似文献   

8.
本课题根据青少年的生理机能特点和运动项目特点,对5名受训的青少年运动员定期测定Vo_(2max)PWC170,血红蛋白,血清睾酮,心腔大小(Dd),心壁厚度(WTd)及其比值(WTd/Dd)等生理生化指标,评定运动员在不同训练阶段的生理机能和运动能力。旨在有序地安排有氧和无氧代谢能力训练,科学地控制训练量与强度,并采用有效的恢复措施,全面提高运动员的身体素质和专项能力,并取得良好的运动成绩。  相似文献   

9.
本文对黑龙江省24名男女少年滑雪运动员进行了PWC_(170)机能试验和最大吸氧量(Vo_2max)的测定,对其结果进行简单分析。少年滑雪运动员肺活量和时间肺活量的均值较高,而且冬季两项滑雪运动员的肺活量和时间肺活量明显较高。这是因为冬季两项运动员的胸肺发育完善,呼吸功能训练良好,通气能力较强。少年越野和冬季两项运动员PWC_(170)和最大吸氧量的均值均无显著性差异。这表明两个项目之间运动员的心血管机能差别不大。少年滑雪运动员PWC_(170)和Vo_2max的均值与国内耐力性项目的少年运动员相比,处于低水平,Vo_2max则明显低于国外少年越野滑雪运动员。这是我国少年滑雪运动员成绩不佳的原因之一。少年滑雪运动员的训练安排应符合他们的解剖和生理特点。早期专项训练应着重全面身体训练及专项素质的训练,不要过早要求出成绩,以免影响身体发育和将来创造优异成绩。  相似文献   

10.
我们的研究是不同的运动方式对摄氧量(Vo_2)、心率、血乳酸和丙酮酸的影响。因此,我们用踏车(TR),功率自行车(up),仰卧式腿测功计(SU)三种运动方式对没有训练过的男性受试者进行了测试。用 TR 测量最大摄氧量的百分数(%V-o_2 max)和 Vo_2/体重比用 up 或 SU 测乳酸水平在2,3和4mmol/1方面有较高的意义。用 TR 测心率比用 SU 测乳酸在2,3和4mmol/1水平同样有较高的意义。血乳酸与%  相似文献   

11.
Traditionally, it has been assumed that during middle-distance running oxygen uptake (VO2) reaches its maximal value (VO2max) providing the event is of a sufficient duration; however, this assumption is largely based on observations in individuals with a relatively low VO2max. The aim of this study was to determine whether VO2max is related to the VO2 attained (i.e. VO2peak) during middle-distance running on a treadmill. Fifteen well-trained male runners (age 23.3 +/- 3.8 years, height 1.80 +/- 0.10 m, body mass 76.9 +/- 10.6 kg) volunteered to participate in the study. The participants undertook two 800-m trials to examine the reproducibility of the VO2 response. These two trials, together with a progressive test to determine VO2max, were completed in a randomized order. Oxygen uptake was determined throughout each test using 15-s Douglas bag collections. Following the application of a 30-s rolling average, the highest VO2 during the progressive test (i.e. VO2max) was compared with the highest VO2 during the 800-m trials (i.e. VO2peak) to examine the relationship between VO2max and the VO2 attained in the 800-m trials. For the 15 runners, VO2max was 58.9 +/- 7.1 ml x kg(-1) x min(-1). Two groups were formed using a median split based on VO2max. For the high and low VO2max groups, VO2max was 65.7 +/- 3.0 and 52.4 +/- 1.8 ml x kg(-1) x min(-1) respectively. The limits of agreement (95%) for test-retest reproducibility for the VO2 attained during the 800-m trials were +/- 3.5 ml x kg(-1) x min(-1) for a VO2peak of 50.6 ml x kg(-1) x min(-1) (the mean VO2peak for the low VO2max group) and +/- 2.3 ml x kg(-1) x min(-1) for a VO2peak of 59.0 ml x kg(-1) x min(-1) (the mean VO2peak for the high VO2max group), with a bias in VO2peak between the 800-m runs (i.e. the mean difference) of 1.2 ml x kg(-1) x min(-1). The VO2peak for the 800-m runs was 54.8 +/- 4.9 ml x kg(-1) x min(-1) for all 15 runners. For the high and low VO2max groups, VO2peak was 59.0 +/- 3.3 ml x kg(-1) x min(-1) (i.e. 90% VO2max) and 50.6 +/- 2.0 ml x kg(-1) x min(-1) (i.e. 97% VO2max) respectively. The negative relationship (-0.77) between VO2max and % VO2max attained for all 15 runners was significant (P = 0.001). These results demonstrate that (i) reproducibility is good and (ii) that VO2max is related to the %VO2max achieved, with participants with a higher VO2max achieving a lower %VO2max in an 800-m trial on a treadmill.  相似文献   

12.
Maximal oxygen uptake VO(2max)) is considered the optimal method to assess aerobic fitness. The measurement of VO(2max), however, requires special equipment and training. Maximal exercise testing with determination of maximal power output offers a more simple approach. This study explores the relationship between [Vdot]O(2max) and maximal power output in 247 children (139 boys and 108 girls) aged 7.9-11.1 years. Maximal oxygen uptake was measured by indirect calorimetry during a maximal ergometer exercise test with an initial workload of 30 W and 15 W x min(-1) increments. Maximal power output was also measured. A sample (n = 124) was used to calculate reference equations, which were then validated using another sample (n = 123). The linear reference equation for both sexes combined was: VO(2max) (ml x min(-1)) = 96 + 10.6 x maximal power + 3.5 . body mass. Using this reference equation, estimated VO(2max) per unit of body mass (ml x min(-1) x kg(-1)) calculated from maximal power correlated closely with the direct measurement of VO(2max) (r = 0.91, P <0.001). Bland-Altman analysis gave a mean limits of agreement of 0.2+/-2.9 (ml x min(-1) x kg(-1)) (1 s). Our results suggest that maximal power output serves as a good surrogate measurement for VO(2max) in population studies of children aged 8-11 years.  相似文献   

13.
The purpose of this study was to assess the validity of predicting the maximal oxygen uptake (VO2(max)) of sedentary men from sub-maximal VO2 values obtained during a perceptually regulated exercise test. Thirteen healthy, sedentary males aged 29-52 years completed five graded exercise tests on a cycle ergometer. The first and fifth test involved a graded exercise test to determine VO2(max). The two maximal graded exercise tests were separated by three sub-maximal graded exercise tests, perceptually regulated at 3-min RPE intensities of 9, 11, 13, 15, and 17 on the Borg ratings of perceived exertion (RPE) scale, in that order. After confirmation that individual linear regression models provided the most appropriate fit to the data, the regression lines for the perceptual ranges 9-17, 9-15, and 11-17 were extrapolated to RPE 20 to predict VO2(max). There were no significant differences between VO2(max) values from the graded exercise tests (mean 43.9 ml x kg(-1) x min(-1), s = 6.3) and predicted VO2(max) values for the perceptual ranges 9-17 (40.7 ml x kg(-1) x min(-1), s = 2.2) and RPE 11-17 (42.5 ml x kg(-1) x min(-1), s = 2.3) across the three trials. The predicted VO2(max) from the perceptual range 9-15 was significantly lower (P < 0.05) (37.7 ml x kg(-1) x min(-1), s = 2.3). The intra-class correlation coefficients between actual and predicted VO2(max) for RPE 9-17 and RPE 11-17 across trials ranged from 0.80 to 0.87. Limits of agreement analysis on actual and predicted VO2 values (bias +/- 1.96 x S(diff)) were 3.4 ml x kg(-1) x min(-1) (+/- 10.7), 2.4 ml x kg(-1) x min(-1) (+/- 9.9), and 3.7 ml x kg(-1) x min(-1) (+/- 12.8) (trials 1, 2, and 3, respectively) of RPE range 9-17. Results suggest that a sub-maximal, perceptually guided graded exercise test provides acceptable estimates of VO2(max) in young to middle-aged sedentary males.  相似文献   

14.
The aim of this study was to determine which physiological variables predict excellence in middle- and long-distance runners. Forty middle-distance runners (age 23 ± 4 years, body mass 67.2 ± 5.9 kg, stature 1.80 ± 0.05 m, VO(2max) 65.9 ± 4.5 ml · kg(-1) · min(-1)) and 32 long-distance runners (age 25 ± 4 years, body mass 59.8 ± 5.1 kg, stature 1.73 ± 0.06 m, VO(2max) 71.6 ± 5.0 ml · kg(-1) · min(-1)) competing at international standard performed an incremental running test to exhaustion. Expired gas analysis was performed breath-by-breath and maximum oxygen uptake (VO(2max)) and two ventilatory thresholds (VT(1) and VT(2)) were calculated. Long-distance runners presented a higher VO(2max) than middle-distance runners when expressed relative to body mass (P < 0.001, d = 1.18, 95% CI [0.68, 1.68]). At the intensities corresponding to VT(1) and VT(2), long-distance runners showed higher values for VO(2) expressed relative to body mass or %VO(2max), speed and oxygen cost of running (P < 0.05). When oxygen uptake was adjusted for body mass, differences between groups were consistent. Logistic binary regression analysis showed that VO(2max) (expressed as l · min(-1) and ml · kg(-1) · min(-1)), VO(2VT2) (expressed as ml · kg(-0.94) · min(-1)), and speed at VT(2) (v(VT2)) categorized long-distance runners. In addition, the multivariate model correctly classified 84.7% of the athletes. Thus, VO(2max), VO(2VT2), and v(VT2) discriminate between elite middle-distance and long-distance runners.  相似文献   

15.
Determinants of success during triathlon competition   总被引:1,自引:0,他引:1  
Eleven male triathletes were studied to determine the relationships between selected metabolic measurements and triathlon performance. Measurements of oxygen uptake (VO2), pulmonary ventilation (VE), and heart rate (HR) were made during submaximal and maximal 365.8 m freestyle swimming (FS), cycle ergometry (CE), and treadmill running (TR). Submaximal workloads were 1 m/s for swimming, 200 W for cycling, and 201.2 m/min for running. The mean VO2 max (l/min) was significantly (p less than .05) lower during FS (4.17) than CE (4.68) or TR (4.81). Swimming, cycling, and running performance times during the Muncie Endurathon (1.2 mile swim, 56 mile cycle, 13.1 mile run) were not significantly related to the event-specific VO2 max (ml/kg/min): -.49, -32 and -.55, respectively. The VO2 max expressed in l/min was found to be significantly (p less than .05) related to cycling time (r = -.70). A significant (p less than .05) relationship was observed between submaximal VO2 (ml/kg/min) during TM and run performance time (r = .64), whereas swimming and cycling performance times were significantly (p less than .05) related to submaximal VO2 max (l/min), r = .72 and .60, respectively. The percentage of VO2 (%VO2 max) used during the submaximal tests was significantly (p less than .05) related to swimming (.91), cycling (.78), and running (.86) performance times. Time spent running and cycling during triathlon competition was significantly (p less than .05) related to overall triathlon time, r = .97 and .81, respectively. However, swimming time was not significantly related (.30) to overall triathlon time. This study suggests that economy of effort is an important determinant of triathlon performance.  相似文献   

16.
The aims of the present study were to assess the maximal oxygen uptake and body composition of adult Chinese men and women, and to determine how these variables relate to age. The cross-sectional sample consisted of 196 men and 221 women aged 20 - 64 years. Maximal oxygen uptake (VO2max) was determined by indirect calorimetry during a maximal exercise test on an electrically braked cycle ergometer. The correlations between VO2max and fat mass were -0.52 in men and -0.58 in women. Linear regression defined the cross-sectional age-related decline in VO2max as 0.35 ml kg(-1) min(-1) year(-1) in men and 0.30 ml kg(-1) min(-1) year(-1) in women. Multiple regression analysis showed that more than 50% of this cross-sectional decline in VO2max was due to fat mass, lean mass, and age. Adding fat mass and lean mass to the multiple regression models reduced the age regression mass from 0.35 to 0.24 ml kg(-1) min(-1) year(-1) in men and from 0.30 to 0.15 ml kg(-1) min(-1) year(-1) in women. We conclude that age, fat mass, and lean mass are independent determinants of maximal oxygen uptake in Chinese adults.  相似文献   

17.
The single-stage treadmill walking test of Ebbeling et al. is commonly used to predict maximal oxygen consumption (.VO(2max)) from a submaximal effort between 50% and 70% of the participant's age-predicted maximum heart rate. The purpose of this study was to determine if this submaximal test correctly predicts .VO(2max) at the low (50% of maximum heart rate) and high (70% of maximum heart rate) ends of the specified heart rate range for males and females aged 18 - 55 years. Each of the 34 participants completed one low-intensity and one high-intensity trial. The two trials resulted in significantly different estimates of .VO(2max) (low-intensity trial: mean 40.5 ml . kg(-1) . min(-1), s = 9.3; high-intensity trial: 47.5 ml . kg(-1) . min(-1), s = 8.8; P < 0.01). A subset of 22 participants concluded their second trial with a .VO(2max) test (mean 47.9 ml . kg(-1) . min(-1), s = 8.9). The low-intensity trial underestimated (mean difference = -3.5 ml . kg(-1) . min(-1); 95% CI = -6.4 to -0.6 ml . kg(-1) . min(-1); P = 0.02) and the high-intensity trial overestimated (mean difference = 3.5 ml . kg(-1) . min(-1); 95% CI = 1.1 to 6.0 ml . kg(-1) . min(-1); P = 0.01) the measured .VO(2max). The predictive validity of Ebbeling and colleagues' single-stage submaximal treadmill walking test is diminished when performed at the extremes of the specified heart rate range.  相似文献   

18.
Clear criteria for maximal oxygen consumption (VO2max) determination in youth are not available, and no studies have examined this issue in girls. Our purpose was to determine whether different peak heart rate (HRpeak) and peak respiratory exchange ratio (RERpeak) cut points affect girls' (N = 453; M age = 13.3 years, SD = .1) VO2max during a maximal treadmill test. A multivariate analysis of variance revealed VO2max (ml kg(-1) min(-1) differed significantly among HRpeak, 180-189 b min(-1) = 34 (SD = .8), 190-194 bmin(-1) = 35 (SD = .9), 195-199 b min(-1) = 38 (SD = .8), 200-204 b min(-1) = 40 ml kg1 x min(-1) (SD = .8), and > or = 205 bmin(-1) = 42 ml kg1 x min(-1) (SD = .7) but not RERpeak. In studies where evidence of a VO2 plateau was examined, peak oxygen consumption (VO2peak) did not differ between plateau and no-plateau groups. Although our results suggest the association between lower VO2peak and lower peak heart rate is a true cardiovascular limit to aerobic energy production, we cannot rule out participant effort.  相似文献   

19.
We examined the effects of pre-exercise sodium bicarbonate (NaHCO3) ingestion on the slow component of oxygen uptake (VO2) kinetics in seven professional road cyclists during intense exercise. One hour after ingesting either a placebo or NaHCO3 (0.3 g x kg body mass(-1)), each cyclist (age, 25 +/- 2 years; VO2max, 74.7 +/- 5.9 ml x kg(-1) x min(-1); mean +/- s) performed two bouts of 6 min duration at an intensity of 90% VO2max interspersed by 8 min of active recovery. Gas exchange and blood data (pH, blood lactate concentration and [HCO3-]) were collected during the tests. In both bouts, the slow component of VO2 was defined as the difference between end-exercise VO2 and the VO2 at the end of the third minute. No significant difference was found in the slow component of VO2 between conditions in the first (NaHCO3, 210 +/- 69 ml; placebo, 239 +/- 105 ml) or second trial (NaHCO3, 123 +/- 88 ml; placebo, 197 +/- 101 ml). In conclusion, pre-exercise NaHCO3 ingestion did not significantly attenuate the VO2 slow component of professional road cyclists during high-intensity exercise.  相似文献   

20.
Thirty-eight female subjects (M +/ SD = 33 +/- 3.0 years) had VO2max measured on the cycle ergometer (M +/- SD = 37.3 +/- 6.4 ml.kg-1.min-1) and on the treadmill (M +/- SD = 41.3 +/- 6.6 ml.kg-1.min-1). VO2max was estimated for each subject from heart rate (HR) at submaximal workloads on the cycle ergometer using the Astrand-Rhyming nomogram (A/R) and the extrapolation method (XTP). VO2max was also estimated from three field tests: 1.5-mile run (RUN) (independent variable [IV] = time), mile walk (WALK) (IV = time, age, HR, gender, body weight), and the Queens College Step Test (ST) (IV = HR during 5-20 s recovery). Repeated measure ANOVA revealed significant mean differences between the criterion cycle ergometer VO2max versus A/R and XTP (20 and 12% overestimation). The WALK, RUN, and ST VO2max values were not significantly different from the criterion treadmill VO2max. The correlation between criterion VO2max estimated from the WALK and RUN were r = .73 (SEE = 4.57 ml,kg-1.min-1) and r = .79 (SEE = 4.13 ml.kg-1.min-1), respectively. The ST, A/R, and XTP had higher SEEs (13-13.5% of the mean) and lower r s (r = .55 to r = .66). These results suggest both the WALK and RUN tests are satisfactory predictors of VO2max in 30 to 39-year-old females.  相似文献   

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