Maximal lactate steady state in trained adolescent runners

The aims of this study were: (1) to identify the exercise intensity that corresponds to the maximal lactate steady state in adolescent endurance-trained runners; (2) to identify any differences between the sexes; and (3) to compare the maximal lactate steady state with commonly cited fixed blood lactate reference parameters. Sixteen boys and nine girls volunteered to participate in the study. They were first tested using a stepwise incremental treadmill protocol to establish the blood lactate profile and peak oxygen uptake ([Vdot]O₂). Running speeds corresponding to fixed whole blood lactate concentrations of 2.0, 2.5 and 4.0?mmol?·?l^?1 were calculated using linear interpolation. The maximal lactate steady state was determined from four separate 20-min constant-speed treadmill runs. The maximal lactate steady state was defined as the fastest running speed, to the nearest 0.5?km?·?h^?1, where the change in blood lactate concentration between 10 and 20?min was?<0.5?mmol?·?l^?1. Although the boys had to run faster than the girls to elicit the maximal lactate steady state (15.7 vs 14.3?km?·?h^?1, P?<0.01), once the data were expressed relative to percent peak [Vdot]O₂ (85 and 85%, respectively) and percent peak heart rate (92 and 94%, respectively), there were no differences between the sexes (P?>0.05). The running speed and percent peak [Vdot]O₂ at the maximal lactate steady state were not different to those corresponding to the fixed blood lactate concentrations of 2.0 and 2.5?mmol?·?l^?1 (P?>0.05), but were both lower than those at the 4.0?mmol?·?l^?1 concentration (P?<0.05). In conclusion, the maximal lactate steady state corresponded to a similar relative exercise intensity as that reported in adult athletes. The running speed, percent peak [Vdot]O₂ and percent peak heart rate at the maximal lactate steady state are approximated by the fixed blood lactate concentration of 2.5?mmol?·?l^?1 measured during an incremental treadmill test in boys and girls.     

Prediction of maximal lactate steady state in runners with an incremental test on the field

During a maximal incremental ergocycle test, the power output associated with Respiratory Exchange Ratio equal to 1.00 (RER = 1.00) predicts maximal lactate steady state (MLSS). We hypothesised that these results are transferable for runners on the field. Fourteen runners performed a maximal progressive test, to assess the speed associated with RER = 1.00, and several 30 minutes constant velocity tests to determine the speed at MLSS. We observed that the speeds at RER = 1.00, at the second ventilatory threshold (VT2) and at MLSS did not differ (15.7 ± 1.1 km · h?1, 16.2 ± 1.4 km · h?1, 15.5 ± 1.1 km · h?1 respectively). The speed associated with RER = 1.00 was better correlated with that at MLSS (r = 0.79; p = 0.0008) than that at VT2 (r = 0.73; p = 0.002). Neither the concentration of blood lactate nor the heart rate differed between the speed at RER = 1.00 and that at MLSS from the 10th and the 30th minute of the constant velocity test. Bland and Altman analysis showed a fair agreement between the speed at MLSS and that at RER (0.2 ± 1.4 km · h?1). This study demonstrated that the speed associated with RER = 1.00 determined during maximal progressive track running allows a fair estimation of the speed associated with MLSS, markedly decreasing the burden of numerous invasive tests required to assess it.     

全民健身运动处方实用性研究

运动处方包括运动强度、运动持续时间、运动频率以及运动类型。运动处方的制定能改善人体亚健康状态;其目的是在确保人体健康的同时也为患者康复治疗提供科学依据。     

Effect of 12 weeks of training on critical velocity and maximal lactate steady state in swimmers

Abstract

The aim of this study was to determine the effect of 12 weeks of training on the critical velocity and maximal lactate steady state of elite swimmers. The tests to determine critical velocity and maximal lactate steady state were performed before and after 12 weeks of training. Critical velocity after 12 weeks of training was significantly higher than before training (1.45±0.10 m · s^?1 vs. 1.41±0.11 m · s^?1). In contrast, no significant differences in the velocity at maximal lactate steady state were observed before and after training (1.41±0.10 m · s^?1 vs. 1.43±0.10 m · s^?1). There was also a decrease in mean lactate concentration after 12 weeks of training. Before training, the velocity at maximal lactate steady state occurred at 100% of critical velocity, with a mean lactate concentration of 4.34 mmol · l^?1. After training, the velocity at maximal lactate steady state occurred at 98% of critical velocity, with a reduced mean lactate concentration of 3.69 mmol · l^?1. Based on these results, it would appear that 12 weeks of training was enough to promote an increase in critical velocity. Although no significant differences in the velocity at maximal lactate steady state were observed before and after training, the decrease in mean lactate concentration after training demonstrated greater efficiency of the aerobic system, leading to less wear during the tests.     

武汉市全民健身路径使用情况分析

采用多级、整群抽样的方法,对武汉城区208例利用全民健身路径锻炼居民的健身情况和全民健身路径的使用情况进行了调查.结果显示:经常参加锻炼的居民占56.7%,偶尔参加锻炼的占34.6%,年龄间差异有显著性(P＜0.05),参加锻炼的中老年人明显高于中青年;居民的健身多以简便、易学的方式为主;中老年和中青年对全民健身路径的看法不同(P＜0.05),多数老年人对器械满意;很多人不知道器械的使用方法,并且有一定的危险性,原因有无人管理、无保护措施、设计不合理等;锻炼者中患各种慢性疾病的人很多,需要专业人员给予指导.     

芜湖市大众健身的调查和科学性研究

健身运动对改善人体的各种机能和组织有着积极的影响,科学性是大众健身的灵魂。大众健身的科学性主要表现在：1）遵循健身运动而非竞技运动的原则;2）制订科学的运动处方;3）建立科学有效的健身检测与评估体系;4）配备数量适应水平较高的健身运动指导员;5）大力发展布局科学、规范适用和方便群众的公共体育设施。     

健康体适能教学的实验观察

为进一步评估健康体适能的教学效果 ,观察了特定运动处方对受试者心脏功能 (FC)、肌肉力量(ST)和柔软度 (FL)的影响。实验前根据FC、ST和FL的检测结果 ,将 2 4 0名男女医学生随机分成 3个对照组和 3个实验组。对照组按原教学进度上体育课 ,实验组以提高健康体适能为教学目标 ,以特定的运动处方进行教学和锻炼。结果显示 ,3个实验组FC、ST和FL指标明显增强 ,且有统计学意义 (P <0 .0 5 )。说明为健康体适能教学所制定的运动处方适用于普通院校大学生的体育教学 ,并可收到良好的效果。     

不同类型健身运动处方对大学生身体素质的影响

为提高大学生的身体机能和运动素质，使学生有针对性地进行课外健身运动锻炼，本研究制定以发展人体柔韧、耐力、力量、灵敏、速度、增重、全面发展及瘦身为主要内容的八类共15套健身运动处方，并在大学课外活动中进行处方锻炼实验，探讨各类健身运动处方锻炼对大学生身体素质的影响。结果表明，本实验制定的各类健身运动处方能有效的提高大学生的身体素质，增进健康，而且不同的健身运动处方对大学生身体素质的影响不同。     

全民健身运动处方的实用性

从运动处方研究的科学基础出发探讨健身活动手段和方式的多样化，阐述运动处方制定的基本原理及理论体系，从中找出制定运动处方的基本规律和原则，以便运动处方能科学地指导健身锻炼。     

Validity and reliability of rating perceived exertion in women with fibromyalgia: exertion-pain discrimination

The present study aimed (1) to assess the validity and reliability of the Borg category-ratio (CR-10) scale for monitoring exercise intensity in women with fibromyalgia (FM) and (2) to examine whether women with FM can discriminate between perceived exertion and exercise-induced pain. Thirty-three women with FM performed two incremental treadmill tests (1 week separated). Heart rate, oxygen uptake, minute ventilation and respiratory quotient were measured. The ratings of perceived exertion (RPE: CR-10 scale) and exercise-induced pain were obtained at each workload. The Spearman’s correlation of RPE with the physiological responses ranged from 0.69 to 0.79. The regression models explained ~50% of the variability of the studied physiological responses. We found “perfect acceptable” agreement in 69% of the observations. Weighted Kappa was 0.66 (95% confidence interval [CI]: 0.59–0.72). There were differences between RPE and pain at workloads 3 (1.50; 95%CI: 0.85–2.16), 4 (2.10; 95%CI: 1.23–2.96), 5 (3.40; 95%CI: 1.29–5.51) and 6 (3.97; 95%CI: 1.61–6.33). The main findings of the present study suggest that the Borg CR-10 scale is valid and moderately reliable for monitoring exercise intensity in women with FM, and these patients were able to discriminate between exertion and exercise-induced pain.     

健美运动处方教学对大学生健身意识和课外锻炼的影响

通过在高校健美课中进行运动处方教学的应用研究,探讨健美运动处方教学对大学生健身意识和课外锻炼的影响j研究结果表明：运动处方教学对大学生科学健身意识的形成有重要的影响作用;运动处方教学能有效提高大学生自我锻炼能力,更好地指导学生进行课外锻炼,对大学生体育锻炼习惯的形成具有积极的影响作用。     

不同运动处方对青少年健康体适能的影响

为了解不同运动处方对青少年健康体适能的影响,寻求对青少年健康体适能的有效干预手段,采用实验法、文献法和数理统计法随机选取高中男女学生共60名作为实验对象,分组进行运动干预,通过八周的实验,发现有氧运动＋力量训练比单纯的有氧运动能更有效的提高青少年的健康体适能。     

Maximal oxygen uptake versus maximal power output in children

Abstract

Maximal oxygen uptake ([Vdot]O_2max) is considered the optimal method to assess aerobic fitness. The measurement of [Vdot]O_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 · 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: [Vdot]O_2max (ml · min^?1) = 96 + 10.6 · maximal power + 3.5 · body mass. Using this reference equation, estimated [Vdot]O_2max per unit of body mass (ml · min^?1 · kg^?1) calculated from maximal power correlated closely with the direct measurement of [Vdot]O_2max (r = 0.91, P <0.001). Bland-Altman analysis gave a mean limits of agreement of 0.2±2.9 (ml · min^?1 · kg^?1) (1 s). Our results suggest that maximal power output serves as a good surrogate measurement for [Vdot]O_2max in population studies of children aged 8–11 years.     

吸高氧对赛艇运动员大强度运动后血乳酸、酸碱度的影响

观察赛艇运动员运动后吸入高氧对乳酸(La)、碳酸氢根离子(HCO3^-)和pH值的影响，实验使用测功仪，在15min内划完4000m的运动负荷，测试吸氧量(VO2)、心率(HR)、血La、血pH值和HCO3^-浓度。结果表明，吸氧组与不吸氧组相比，吸氧组血La、pH值恢复得较快，并在运动后5、10min有显性差异；同样吸氧组HCO3^-恢复得较快，且在运动后20、30min有显性差异。结果提示，运动后吸氧可能改善体内酸性环境，加快乳酸的消除，有助于机体的恢复。     

北京市全民健身路径使用情况调查

采用多级、整群抽样的方法 ,对北京城区 190例利用全民健身路径锻炼居民的健身情况和全民健身路径的使用情况进行了调查。结果显示 :经常参加锻炼的居民占 5 7.4 % ,偶尔参加锻炼的占 34.7% ,年龄间差异有显著性 (P <0 .0 5 ) ,参加锻炼的中老年人明显高于中青年 ;居民的健身多以简便、易学的方式为主 ;中老年人和中青年对全民健身路径的看法不同 (P <0 .0 5 ) ,多数老年人对器械满意 ;很多人不知道器械的使用方法 ,并且有一定的危险性 ,原因有无人管理、无保护措施、设计不合理等 ;锻炼者中患各种慢性疾病的人很多 ,需要专业人员给予指导。     

运动处方在高职体育教学中增强学生体质的实践与应用

五年制高职的体育教学改革,必须立足素质教育,以发展学生个性为原则,把发展学生体质,促进学生身心健康作为学校体育工作的首要任务。在体育教学活动中引入运动处方,紧紧围绕着“增强学生体质”这一中心任务,做到有目的、有针对性,达到事半功倍的效果。     

体育锻炼对研究生健康影响的实验研究

通过实验研究体育锻炼对研究生健康和体质的积极影响与促进作用,并揭示不同运动量（强度）的体育锻炼对提高研究生健康和体质的不同效应。     

运动处方中运动强度的确定方法

运用文献综述法,对运动处方中运动强度的确定方法进行归类、分析。指出,运动负荷心电图是比较切实可行的确定运动强度的方法。     

聋哑大学生体质综合测定及健身运动处方的研究

通过对聋哑人在校大学生10 7人进行10项形态、机能、素质指标的测试,针对聋哑大学生特点研制健身运动处方,进行8周实验,对实验前、后主要机能素质进行对比。结果显示,1)聋哑大学生的肺活量、长距离跑都非常显著地劣于普通大学生;2 )本研究设计的“聋生健身运动处方”持续练习8周以后,肺活量、立定跳远、长距离跑、仰卧起坐、引体向上等身体素质显著增长,对于增进聋哑大学生体质和改善他们的心理状态有较大的作用。