A comparison of the physiological response to simulated altitude exposure and r-HuEpo administration

Concerns have been raised about the morality of using simulated altitude facilities in an attempt to improve athletic performance. One assumption that has been influential in this debate is the belief that altitude houses simply mimic the physiological effects of illegal recombinant human erythropoietin (r-HuEpo) doping. To test the validity of this assumption, the haematological and physiological responses of 23 well-trained athletes exposed to a simulated altitude of 2650-3000 m for 11-23 nights were contrasted with those of healthy volunteers receiving a low dose (150 IU·kg^-1 per week) of r-HuEpo for 25 days. Serial blood samples were analysed for serum erythropoietin and percent reticulocytes; maximal oxygen uptake ([Vdot]O_2max) was assessed before and after r-HuEpo administration or simulated altitude exposure. The group mean increase in serum erythropoietin (422% for r-HuEpo vs 59% for simulated altitude), percent reticulocytes (89% vs 30%) and [Vdot]O_2max (6.6% vs -2.0%) indicated that simulated altitude did not induce the changes obtained with r-HuEpo administration. Based on the disparity of these responses, we conclude that simulated altitude facilities should not be considered unethical based solely on the tenet that they provide an alternative means of obtaining the benefits sought by illegal r-HuEpo doping.     

不同性别游泳运动员高原训练生理生化的监控研究

目的：通过对不同性别优秀游泳运动员在高原训练期间生理机能变化特点的研究,总结各生理指标变化规律,制定出运动员生理机能的评定方法,监控运动员高原训练期间的身体机能状况,保证教练员在高原训练期间训练计划的顺利实施。方法：通过血液分析仪、半自动生化分析仪、全自动微粒子化学发光免疫分析仪等,对运动员的基本生理、生化指标进行监控。每周测定一次运动员安静时红细胞计数、血球压积、血红蛋白、肌酸激酶、尿素氮和睾酮值。结果：高原训练期间血液成分RBC、Hb、Hct明显升高,女性增高幅度大于男性;下高原后与上高原前相比,血液成分男性无显著性差异,女性明显高于上高原前;男性在整个高原训练期肌酸激酶（CK）和睾酮（T）均无显著性差异,尿素氮（BUN）仅在高原训练第4周和下高原后有差异;女性CK值在高原训练第3周、第4周和下高原后存在差异,BUN均存在显著性差异,T下高原后存在差异。结论：高原训练对提高血液成分RBC、Hb、Hct效果显著,且对女性的持续效应要高于男性。BUN可作为高原训练期间评价女性机能状态和训练负荷的敏感指标。     

Effect of suspension systems on the physiological and psychological responses to sub-maximal biking on simulated smoothand bumpy tracks

The aim of this study was to compare the physiological and psychological responses of cyclists riding on a hard tail bicycle and on a full suspension bicycle. Twenty males participated in two series of tests. A test rig held the front axle of the bicycle steady while the rear wheel rotated against a heavy roller with bumps (or no bumps) on its surface. In the first series of tests, eight participants (age 19-27 years, body mass 65-82 kg) were tested on both the full suspension and hard tail bicycles with and without bumps fitted to the roller. The second series of test repeated the bump tests with a further six participants (age 22-31 years, body mass 74-94 kg) and also involved an investigation of familiarization effects with the final six participants (age 21-30 years, body mass 64-80 kg). Heart rate, oxygen consumption (VO(2)), rating of perceived exertion (RPE) and comfort were recorded during 10 min sub-maximal tests. Combined data for the bumps tests show that the full suspension bicycle was significantly different (P < 0.001) from the hard tail bicycle on all four measures. Oxygen consumption, heart rate and RPE were lower on average by 8.7 (s = 3.6) ml . kg(-1) . min(-1), 32.1 (s = 12.1) beats . min(-1) and 2.6 (s = 2.0) units, respectively. Comfort scores were higher (better) on average by 1.9 (s = 0.8) units. For the no bumps tests, the only statistically significant difference (P = 0.008) was in VO(2), which was lower for the hard tail bicycle by 2.2 (s = 1.7) ml . kg(-1) . min(-1). The results indicate that the full suspension bicycle provides a physiological and psychological advantage over the hard tail bicycle during simulated sub-maximal exercise on bumps.     

Effect of suspension systems on the physiological and psychological responses to sub-maximal biking on simulated smoothand bumpy tracks

Abstract

The aim of this study was to compare the physiological and psychological responses of cyclists riding on a hard tail bicycle and on a full suspension bicycle. Twenty males participated in two series of tests. A test rig held the front axle of the bicycle steady while the rear wheel rotated against a heavy roller with bumps (or no bumps) on its surface. In the first series of tests, eight participants (age 19 – 27 years, body mass 65 – 82 kg) were tested on both the full suspension and hard tail bicycles with and without bumps fitted to the roller. The second series of test repeated the bump tests with a further six participants (age 22 – 31 years, body mass 74 – 94 kg) and also involved an investigation of familiarization effects with the final six participants (age 21 – 30 years, body mass 64 – 80 kg). Heart rate, oxygen consumption ([Vdot]O₂), rating of perceived exertion (RPE) and comfort were recorded during 10 min sub-maximal tests. Combined data for the bumps tests show that the full suspension bicycle was significantly different (P < 0.001) from the hard tail bicycle on all four measures. Oxygen consumption, heart rate and RPE were lower on average by 8.7 (s = 3.6) ml · kg^?1 · min^?1, 32.1 (s = 12.1) beats · min^?1 and 2.6 (s = 2.0) units, respectively. Comfort scores were higher (better) on average by 1.9 (s = 0.8) units. For the no bumps tests, the only statistically significant difference (P = 0.008) was in [Vdot]O₂, which was lower for the hard tail bicycle by 2.2 (s = 1.7) ml · kg^?1 · min^?1. The results indicate that the full suspension bicycle provides a physiological and psychological advantage over the hard tail bicycle during simulated sub-maximal exercise on bumps.     

游泳运动员高原训练部分生理、生化指标的变化分析

高原训练可以提高运动员的运动能力,应用血氧饱和度、晨脉、体重及部分血液指标对高原训练进行科学的监控,可以了解运动员对运动训练的适应和恢复情况。     

A comparison of physiological and anthropometric characteristics among playing positions in sub-elite rugby league players

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.     

模拟交替低氧训练对大鼠心肌相关生理生化指标的影响

模拟高原训练是能够避免高原训练弊端,最大程度激发机体生理潜能,提高运动员竞技水平的有效方法。本研究尝试从设计交替训练的海拔高度着手,通过应用人工低压氧舱模拟高原训练方法,建立固定海拔2500m、4000m以及2500m～4000m交替低氧训练的动物模型,通过应用生理和生化方法对大鼠心肌相关指标进行检测及研究分析,探讨不同海拔及交替海拔训练条件下大鼠心肌抗氧化能力、有氧代谢能力等的变化,从而为运动员高——高交替训练提供参考。实验以雄性Wister大鼠为实验对象,以递增负荷跑台训练方式建立动物训练模型。将筛选后的大鼠随机分为：常氧运动组、2500m低氧运动组、4000m低氧运动组、交替低氧运动组,每组8只。第1周到第4周各组分别以不同的跑台训练模型进行训练,下高原后第5天以25m／min的速度跑至力竭。全部断头处死后,取心肌组织,分别测试各组大鼠心肌中SOD、MDA、SDH、LDH、Ca^2＋-ATP酶活性的变化。实验结果表明：经过4周不同海拔低氧递增负荷跑台训练及下高原后4天的训练,交替低氧运动组大鼠心肌各指标,如SOD、SDH、Ca^2＋-ATP酶活性均高于其他各组,MDA低于其他各组,LDH活性组间无显著性变化。说明交替低氧训练既可以维持较高海拔的低氧刺激,又可以减少过高海拔造成的损伤,有利于机体恢复。     

浅析高原反应的克服与适应

从机体的生理特性和高原环境因素展开综述相关文献,总结了目前应用于实践的高原训练方式手段,以应用于克服和适应高原反应.     

Effects of neuromuscular function and split step on reaction speed in simulated tennis response

Abstract

The purpose of this study was to examine whether split step (small hop before step) would be more beneficial than no-split condition in simulated tennis response situation. In addition, it was studied if movement time of the response is related to separately measured force production capabilities and reflex sensitivity of the players. Nine skilled male tennis players participated in this study. Subjects stood on a force plate and reacted to a light signal and moved to appointed direction as fast as possible. With split step the participants were 13.1% faster (P <0.05) than without split step from the start to the distal end of the so called close range movement continuum (2.70 m). This was mainly explained by 43.6% faster time (P <0.05) from the signal to the onset of force production. Greater vertical forces were observed with split step: 15.7% greater F(z) mean force (P <0.05), 60.0% greater F(z) peak force (P<0.01). In split step both mean (r= ? 0.813, P <0.01) and peak (r=?0.765, P <0.05) vertical forces (Fz) correlated negatively with the time from the onset of the force production to the photocell. With split step higher EMGs were observed in muscles responsible for ankle joint movement indicating that different strategies were used. Due to the split step the players were able to start the movement faster which mostly explains the advantages over the no-split step condition. Split step condition may also benefit from stretch shortening type of muscle action.     

发展有氧耐力的生理学分析

有氧耐力是指机体从事长时间运动的重要能力，有氧训练可以有效地改善机体的心肺功能，提高神经系统的协调性，发展有氧耐力。本主要阐明了发展有氧耐力的生理学依据以及发展有氧耐力的控制原则。     

对体育教师实施"能本管理"的研究

科学管理体育师资队伍,充分发挥每个体育教师的工作潜能,是全面提高学校素质教育质量的重要保证。从怎样培养体育教师的工作能力、激发体育教师工作的潜力及发挥好他们的聪明才智三方面论述了“能本管理”的概念、模式及对现实的重要意义。     

华南地区高校体育课生理负荷强度比较分析

采用遥测技术、多项式拟合与聚类分析等方法,对华南地区7所高等院校体育课的运动生理负荷强度进行了现场测试和分析.结果显示丰富体育课内容、强化学生体能训练是华南地区体育课改革的一个突出特点;课的总体平均生理负荷强度(用心率指标表示)为142次/min,其中男女生分别为144次/min和137次/min.与全国平均水平相比,无显著性差异(P＞0.05).     

退休体育教师传媒接触状况的调查与分析

在人口老龄化背景下,对退休体育教师接触电视、广播、报纸、杂志及网络媒介的行为、动机、偏好及感受等进行的调查分析显示,传媒接触是大多数退休体育教师闲暇生活的主导活动,是他们与社会互动的主要中介;退休体育教师对不同媒介的接触程度有很大差异;性别、年龄、经济状况及健康状况等因素对退休体育教师传媒接触有不同程度的影响;退休体育教师传媒接触的动机、偏好及感受具有值得关注的特点。改善传媒接触是应对人口老龄化问题的重要途径。     

不同强度模拟低氧训练对网织红细胞及其参数的影响

目的：研究不同强度模拟低氧训练后大鼠红细胞及其参数的变化,探讨不同强度模拟低氧训练对骨髓造血功能的影响。方法：将SD大鼠随机分为16小组,其中常氧跟低氧各8组且一一对应。5周中强度训练、6周高强度训练后,检测大鼠网织红细胞及其参数的变化情况。结果显示：仅接收低氧刺激,不会使骨髓造血状况有显著改变;但进行高强度训练会使幼稚网红含量明显增多,骨髓红细胞比较活跃;两种氧环境中训组和高训组运动后基础状态下,网红含量都没有发生明显改变,高训组在运动后即刻骨髓造血功能是受到抑制的;低氧环境下,一次高强度运动后骨髓造血功能受到抑制,进行中强度训练会显著提高骨髓造血状况,进行极限强度运动后,网红活跃度明显降低。     

格斗类重竞技项目高原训练的可行性分析

结合文献分析和理论思考讨论了格斗类重竞技项目代谢特点,高原训练对格斗类重竞技项群有氧代谢系统、无氧代谢系统的训练学效应以及体重控制和力量等身体素质等方面的积极的训练学效应以及高原训练的有关不利因素,基于高原训练的利弊分析提出通过系统地设计高原训练计划,研究制定有别于平原训练方法的高原训练模式是可以实现扬长避短,充分发挥高原训练的积极效应,有效控制与避免不利影响,从而达到积极的高原训练目的.     

Effect of intermittent normobaric hypoxic exposure at rest on haematological, physiological, and performance parameters in multi-sport athletes

The aim of this study was to determine whether 3 weeks of intermittent normobaric hypoxic exposure at rest was able to elicit changes that would benefit multi-sport athletes. Twenty-two multi-sport athletes of mixed ability were exposed to either a normobaric hypoxic gas (intermittent hypoxic training group) or a placebo gas containing normal room air (placebo group). The participants breathed the gas mixtures in 5-min intervals interspersed with 5-min recovery periods of normal room air for a total of 90 min per day, 5 days per week, over a 3-week period. The oxygen in the hypoxic gas decreased from 13% in week 1 to 10% by week 3. The training and placebo groups underwent a total of four performance tests, including a familiarization and baseline trial before the intervention, followed by trials at 2 and 17 days after the intervention. Time to complete the 3-km run decreased by 1.7%[95% confidence interval (CI) = -0.6 - 3.9%] 2 days after, and by 2.3% (CI = 0.25 - 4.4%) 17 days after, the last hypoxic episode in the training relative to the placebo group. Substantial changes in the training relative to the placebo group also included increased reticulocyte count 2 days (23.5%; CI =-1.9 to 44.9%) and 12 days (14.6%; CI = -7.1 to 36.4%) post-exposure. The effect of intermittent hypoxic training on 3-km performance found in this study is likely to be beneficial, which suggests non-elite multi-sport athletes should expect such training to enhance performance.     

Comparison of physiological responses to morning and evening submaximal running

The aim of this study was to assess the effect of time of day on physiological responses to running at the speed at the lactate threshold. After determination of the lactate threshold, using a standard incremental protocol, nine male runners (age 26.3 - 5.7 years, height 1.77 - 0.07 m, mass 73.1 - 6.5 kg, lactate threshold speed 13.6 - 1.6 km· h -1 ; mean - s ) completed a standardized 30 min run at lactate threshold speed, twice within 24 h (07:00- 09:00 h and 18:00-21:00 h). Core body temperature, heart rate, minute ventilation, oxygen uptake, carbon dioxide expired, respiratory exchange ratio and capillary blood lactate were measured at rest, after a warm-up and at 10, 20 and 30 min during the run. In addition, the rating of perceived exertion was reported every 10 min during the run. Significant diurnal variation was observed only for body temperature (36.9 - 0.9°C vs 37.3 - 0.3°C) and respiratory exchange ratio at rest (0.86 - 0.01 vs 0.89 - 0.07) ( P ? 0.05). Diurnal variation persisted for body temperature throughout the warm-up (37.1 - 0.2°C vs 37.5 - 0.3°C) and during exercise (36.2 - 0.6°C vs 38.6 - 0.4°C), but only during the warm-up for the respiratory exchange ratio (0.85 - 0.05 vs 0.87 - 0.02) ( P ? 0.05). The rating of perceived exertion was significantly elevated during the morning trial (12.7 - 0.9 vs 11.9 - 1.2) ( P ? 0.05). These findings suggest that, despite the diurnal variation in body temperature, other physiological responses to running at lactate threshold speed are largely unaffected. However, a longer warm-up may be required in morning trials because of a slower increase in body temperature, which could have an impact on ventilation responses and ratings of perceived exertion.     

Comparison of physiological responses to morning and evening submaximal running

The aim of this study was to assess the effect of time of day on physiological responses to running at the speed at the lactate threshold. After determination of the lactate threshold, using a standard incremental protocol, nine male runners (age 26.3 +/- 5.7 years, height 1.77 +/- 0.07 m, mass 73.1 +/- 6.5 kg, lactate threshold speed 13.6 +/- 1.6 km x h(-1); mean +/- s) completed a standardized 30 min run at lactate threshold speed, twice within 24 h (07:00-09:00 h and 18:00-21:00 h). Core body temperature, heart rate, minute ventilation, oxygen uptake, carbon dioxide expired, respiratory exchange ratio and capillary blood lactate were measured at rest, after a warm-up and at 10, 20 and 30 min during the run. In addition, the rating of perceived exertion was reported every 10 min during the run. Significant diurnal variation was observed only for body temperature (36.9 +/- 0.9 degrees C vs 37.3 +/- 0.3 degrees C) and respiratory exchange ratio at rest (0.86 +/- 0.01 vs 0.89 +/- 0.07) (P < 0.05). Diurnal variation persisted for body temperature throughout the warm-up (37.1 +/- 0.2 degrees C vs 37.5 +/- 0.3 degrees C) and during exercise (36.2 +/- 0.6 degrees C vs 38.6 +/- 0.4 degrees C), but only during the warm-up for the respiratory exchange ratio (0.85 +/- 0.05 vs 0.87 +/- 0.02) (P < 0.05). The rating of perceived exertion was significantly elevated during the morning trial (12.7 +/- 0.9 vs 11.9 +/- 1.2) (P < 0.05). These findings suggest that, despite the diurnal variation in body temperature, other physiological responses to running at lactate threshold speed are largely unaffected. However, a longer warm-up may be required in morning trials because of a slower increase in body temperature, which could have an impact on ventilation responses and ratings of perceived exertion.