急性低氧对自行车运动员递增负荷运动时肌氧饱和度的影响   总被引：1，自引：1，他引：0  

何琳  徐飞  马国东  李岳  腾轶超 《天津体育学院学报》2010,25(6):478-481

目的:通过近红外光谱技术观察自行车运动员低氧下递增负荷运动时肌氧饱和度的变化,探索可靠、有效,无创的评价肌肉疲劳指标.方法:连续监测15名自行车运动员常氧和急性低氧环境下递增负荷运动时心肺系统和肌氧饱和度的变化.结果:(1)低氧条件下,由开始运动到75%最大功率,△[HbO2]降低、△[HHb]增高;由75%至100%最大功率时,△[HbO2]保持不变,△[HHb]和△[THb]增加.但在4个不同功率等级下低氧△[HbO2]均高于常氧值,△[HHb]存50%、75%和100%最大功率时均低于常氧对应值;(2)运动员在低氧运动时,无氧阈(VT)和最大摄氧量(VO2max)出现时对应的心率、气体代谢、血氧饱和度(SpO2)和功率都出现降低;其中VT和VO2max/对应的VO2、VE/VO2、VE/VCO2和SpO2都低于常氧运动时的值.结论:(1)自行车运动员低氧运动时相对强度增大,而低氧通气反应显著高于常氧水平.提示提高自行车运动员在高原训练和/或比赛时的低氧通气反应有利于提高其有氧能力;(2)低氧运动时△[HbO2]显著高于常氧值,△[HHb]显著低于常氧值,说明肌氧饱和度是反映肌肉疲劳程度的敏感指标,可考虑将其作为监控和评价白行车运动员训练、比赛的指标.  相似文献   

高水平公路自行车运动员急性低氧运动时脑氧饱和度变化特征研究     

徐飞  马国东  李岳 《天津体育学院学报》2012,27(3):214-218

目的:通过近红外光谱学技术观察公路自行车运动员急性低氧运动时脑氧饱和度变化特征,以期为该项目科学化训练提供参考.方法:采用交叉设计,15名优秀公路赛自行车运动员(9男6女)于常氧和急性低氧环境下进行递增负荷运动,运动过程中连续监测其通气功能、动脉血氧饱和度和脑组织氧饱和度的变化.结果:(1)运动员低氧下出现无氧阈和最大摄氧量时对应的通气指标和血氧饱和度都显著低于常氧对应值.(2)低氧下,从开始运动到力竭时脑氧饱和度呈△[02Hb]降低、△[HHb]和△[THb]升高的趋势.在25％、50％、75％和100％相对功率等级时,△[O2Hb]和△[THb]显著低于常氧值,△[HHb]显著高于常氧值.△[THb]在75％～100％最大功率阶段,脑氧变化较小.(3)低氧下,相对功率和绝对功率对应的脑氧饱和度都显著大于常氧对应值.结论:自行车运动员常氧运动时脑氧饱和度在50％ ～ 75％最大功率区间维持在较高水平,而低氧下脑氧饱和度显著降低.低氧时相对运动强度变大、运动低氧血症(EIAH)和通气不足可能是脑氧显著降低的直接原因.故提高自行车运动员低氧通气反应有利于提高其脑氧饱和度,从而提高其有氧能力和运动成绩.  相似文献   

用近红外光谱学技术无损监测气体交换率的新途径探讨   总被引：1，自引：0，他引：1  

徐国栋  高辛琳  刘明  吕坤如  龚辉 《武汉体育学院学报》2004,38(4):46-49

为了探讨等级性递增强度运动过程中骨骼肌组织内肌氧含量相对变化的特点,以及氧合血红蛋白含量的相对变化(ΔHbO2)与运动强度和通气无氧阈(VT)间的关系,利用基于光漫射理论研制的三波长近红外肌氧测量系统,对10名男子中长跑运动员在跑台上作7级递增强度运动时肌氧含量的相对变化进行了在体、实时、连续监测,同时测定了受试者的VO2、二氧化碳呼出量(VCO2)、HR和RER等参数。研究结果表明,运动过程中骨骼肌组织内肌氧含量随着运动强度的增加呈现出规律性的变化,ΔHbO2与VO2和VT间具有高度的相关性。  相似文献   

肌氧含量的相对有效下降值与最大摄氧量的对比研究   总被引：4，自引：0，他引：4  

沈友清  王建珍  徐国栋 《武汉体育学院学报》2007,41(1):58-60,77

采用近红外无损肌氧监测系统，对赛艇运动员在递增强度运动时骨骼肌组织中肌氧的变化进行监测，测定不同运动员的肌氧含量相对有效下降值（Deff），并测定最大摄氧量（VO2max）。将监测到的Deff与VO2max的变化作对比研究，以期探讨骨骼肌组织中肌氧含量的相对变化与VO2max的变化规律及相关关系。研究结果显示运动中肌氧含量的相对有效下降值与最大摄氧量存在相关性，这为用无损伤技术监测人体运动时氧化代谢能力提供了新的途径。  相似文献   

运动后低氧暴露对血液流变学及红细胞形态的影响   总被引：4，自引：0，他引：4  

包大鹏  胡扬  田野  雷雨晨  河春姬 《体育科学》2005,25(4):28-31

研究目的：观察常氧运动后低氧暴露情况下血液流变学及红细胞形态的变化。研究方法：8名受试者以75％ VO2max强度分别完成2次1h蹬功率自行车运动，间隔1周。第1周受试者以75％ VO2max强度蹬功率自行车1h后即进入低氧室内(氧气浓度：15．4％，相当于海拔2500m)休息30min。第2周同一时间，受试者以同等负荷运动1h后常氧环境休息30min。每次实验分别于安静时、运动后即刻、运动后30min采取静脉血5ml，测血液流变学变化和扫描电镜(SEM)下观察红细胞形态变化。结果：运动后血液粘度升高，红细胞变形能力下降，红细胞形态由双凹圆盘状变为单侧凹陷另一侧隆起似礼帽状的I型口形红细胞。结论：运动后低氧暴露不利于血液流变学及红细胞形态的恢复。  相似文献   

递增强度运动过程中NIRS肌氧拐点在评价人体最大有氧能力中的作用     

张立  宋高晴 《武汉体育学院学报》2011,45(1)

应用近红外光谱技术(NIRS)测定肌肉递增强度工作时肌氧含量变化与最大摄氧量和无氧阈指标之间的关系;分析肌氧拐点与无氧阈拐点产生的机制及在测定最大有氧能力中的作用。方法:受试者17名按运动水平分为A、B两组在功率自行车上以逐级递增负荷蹬车,测定右股外侧肌肌氧含量并同步测量VE、VCO2、VO2、HR,并在每级负荷末测定血乳酸。结果:研究发现递增负荷运动时肌氧含量呈台阶状下降,负荷较低时,肌氧在负荷开始阶段迅速下降之后保持平衡或升高,负荷较高时肌氧持续下降,肌氧的变化与血容量相吻合。肌氧含量与摄氧量、心率及血乳酸等值高度相关(P<0.01)。肌氧下降时出现拐点与乳酸阈、通气阈拐点基本一致。结论:研究表明NIRS测定动态肌肉收缩时肌氧含量变化对运动强度具有较高敏感性;肌氧拐点与通气无氧阈、心率无氧阈、乳酸阈在时间和强度上相一致,表明肌氧含量的测定可以用于人体最大有氧能力的评定。  相似文献   

急性低氧运动对摔跤运动员白细胞凋亡的影响     

包大鹏  夏志悦  赵琳琳  胡扬 《中国体育科技》2009,45(4)

目的:通过观察低氧运动前、后白细胞凋亡与计数的变化,探讨低氧运动对白细胞数量与功能的影响.方法:8名男子摔跤运动员在氧浓度为15.4%(相当于海拔2 500 m高度)的低氧环境进行75%VO2max强度功率自行车运动1 h,运动前和运动后即刻取静脉血(EDTA抗凝)采用流式细胞仪测定外周血淋巴细胞中凋亡细胞和活细胞百分比,并应用全自动血细胞分析仪测定白细胞计数和淋巴细胞计数.结果:急性低氧运动后白细胞计数和淋巴细胞计数均显著性增加(P<0.01),分别从6.59±1.44增至10.64±2.97,2.16±0.69增至3.86±1.09;淋巴细胞中凋亡细胞从11.17%±2.65%增至18.84%±3.05%,活细胞百分比从88.37%±2.70%下降至85.67%±3.02%,两者均有显著性差异.结论:急性低氧运动可导致机体白细胞计数和淋巴细胞计数增加,淋巴细胞中凋亡细胞和活细胞等比例变比.  相似文献   

模拟4800m低氧环境训练的适应效果研究     

潘秀清 《沈阳体育学院学报》2012,31(3):62-65

目的:对20名平原受试者进行为期3周递增性低氧训练,测试其低氧训练前后模拟海拔4 800m(PO2为10.4%～10.8%)时血清抗利尿激素(AVP)和醛固酮(ALD)的变化,并结合AMS评分、心率和血压,探讨递增性低氧训练对模拟高海拔低氧环境的适应效果。方法:阶段1:受试者于模拟海拔4 800m低氧环境中急性暴露6 h,以60rpm、80 W的定量负荷仰卧蹬车20 min,LLS量表评价AMS,测试低氧暴露过程中的HR和BP,低氧结束时的血清AVP和ALD;阶段2:进行3周递增性低氧训练后,再重复阶段1的测试。结果:低训后模拟海拔4 800m低氧环境下,AMS评分大于等于3分的人数由9人降到2人;运动时的心率明显低于低训前;急性低氧暴露6h,血清AVP和ALD均较常氧值显著下降;低训3周后再次低氧暴露,血清AVP和ALD与常氧值相比较,均无显著差异。结论:递增性低氧训练有助于增强机体对低氧的习服。  相似文献   

划船运动员静力及动力性肌肉运动疲劳时肌氧含量的变化特征及对EMG参数的影响     

张立  宋高晴 《体育科学》2006,26(3):53-57

研究目的：1）研究静力和动力性肌肉运动疲劳时肌肉氧含量的变化特点厦其规律；2）了解静力性、动力性递增强度运动时EMG参数变化；3）探讨肌氧含量与EMG参数变化之间的关系，为肌肉疲劳时影响肌电肌氧机制提供可能的理论基础。研究方法：1）肌氧含量的测试：探头纵向旋转让光源和检测器的轴线平行于股外侧肌外侧头大腿测定运动时肌氧含量的变化；2）肌电的测试：采用表面肌电图的测量，得出表面电图各指标参数；3）静力负荷等长收缩：通过力量传感器测出其最大肌肉收缩所对应的MVC；4）动力性负荷运动：采取功率自行车逐级递增负荷的测试方法作为肌肉的动力性运动，同步记录EMG参数，并在每一级负荷朱30S采血测定血乳酸浓度。结论：静力性运动时E／T值大幅度增大的时间大多出现在肌氧停止下降之后，肌氧的降低程度与肌肉疲劳程度有关。动力性运动时血乳酸值随负荷而增加，IEMG的变化趋势与血乳酸相似，IEMG、Oxy-Hb、BI值三者呈非常显著性相关，表明肌肉疲劳时肌肉氧供和内环境的改变也是影响EMG信号的重要因素。  相似文献   

急性低氧暴露对足球运动员甲襞微循环的影响   总被引：1，自引：0，他引：1  

谌晓安  胡扬  王琳  田野 《西安体育学院学报》2007,24(4):80-84

目的观察急性低氧暴露对足球运动员甲襞微循环的影响及探讨可能的机制。方法让8名北京体育大学体育系男子足球专项运动员晚上在低氧房暴露居住10 h。低氧房中氧含量为15.3%(相当于海拨2500 m)。分别于低氧暴露前1天、急性低氧暴露10 h后测试安静时和定量运动负荷后甲襞微循环的变化。结果急性低氧暴露后,(1)安静时形态积分较高,运动后10 min、15 min的形态积分均比安静时明显降低(P<0.05);(2)运动后即刻的流态积分、总积分均显著高于安静时(P<0.05);(3)运动后5 min、10 min及15 min时,血流速逐渐加快,红细胞聚集程度减轻,积分值降低(P<0.05)。结论急性低氧暴露后,甲襞微循环出现明显的代偿性变化。  相似文献   

急性缺氧暴露情况下运动对中动脉脑血流速度的影响   总被引：1，自引：0，他引：1  

梁丽娟  熊开宇  田野  胡扬  孔兆伟  陈效科 《体育科学》2005,25(11):40-42

利用常压低氧屋模拟2500m高原急性缺氧，测试了6名世居平原的男子在常氧和急性缺氧情况下，中等强度运动前后中动脉经颅多普勒血流速度的变化。结果显示，急性缺氧暴露情况下，安静时平均脑血流速度（Vm）、收缩期血流速度（Vp）和舒张期血流速度（Vd）从第5min到第20min都持续上升，且Vd增加幅度最大。常氧和急性缺氧运动后即刻，Vm和Vp均显著增加，常氧运动后Vm、Vp的增加幅度均高于急性缺氧运动后；常氧运动后Vd增加，而急性缺氧运动后Vd略有降低。提示，急性缺氧主要通过调节脑血管阻力增加舒张期血流速度，从而增加脑血流量来满足动脉氧含量下降时大脑的供氧需求；急性缺氧运动与常氧运动一样，都是通过增加收缩期血流速度来满足大脑供氧需求，但急性缺氧暴露抑制了运动对脑血流速度的增加效应；与常氧运动、急性缺氧相比，急性缺氧运动对舒张期血流速度的影响比对平均脑血流速度和收缩期血流速度的影响要大。  相似文献   

Normobaric hypoxia increases the growth hormone response to maximal resistance exercise in trained men     

Dean Filopoulos  Stuart J. Cormack 《European Journal of Sport Science》2017,17(7):821-829

This study examined the effect of hypoxia on growth hormone (GH) release during an acute bout of high-intensity, low-volume resistance exercise. Using a single-blinded, randomised crossover design, 16 resistance-trained males completed two resistance exercise sessions in normobaric hypoxia (HYP; inspiratory oxygen fraction, (FiO₂) 0.12, arterial oxygen saturation (SpO₂) 82?±?2%) and normoxia (NOR; FiO₂ 0.21, SpO₂ 98?±?0%). Each session consisted of five sets of three repetitions of 45° leg press and bench press at 85% of one repetition maximum. Heart rate, SpO₂, and electromyographic activity (EMG) of the vastus lateralis muscle were measured throughout the protocol. Serum lactate and GH levels were determined pre-exposure, and at 5, 15, 30 and 60?min post-exercise. Differences in mean and integrated EMG between HYP and NOR treatments were unclear. However, there was an important increase in the peak levels and area under the curve of both lactate (HYP 5.8?±?1.8 v NOR 3.9?±?1.1?mmol.L^?1 and HYP 138.7?±?33.1 v NOR 105.8?±?20.8?min.mmol.L^?1) and GH (HYP 4.4?±?3.1 v NOR 2.1?±?2.5?ng.mL^?1 and HYP 117.7?±?86.9 v NOR 72.9?±?85.3?min.ng.mL^?1) in response to HYP. These results suggest that performing high-intensity resistance exercise in a hypoxic environment may provide a beneficial endocrine response without compromising the neuromuscular activation required for maximal strength development.  相似文献   

不同训练强度对间歇性缺氧大鼠骨骼肌NO和NOS的影响   总被引：6，自引：0，他引：6  

丁宁炜  张红品  秦学林  汤强  姜文凯 《体育与科学》2007,28(1):69-71

利用低氧舱技术模拟“高住低练”环境,观察间歇性缺氧条件和两种不同运动训练强度对骨骼肌NO和NOS的共同作用效应。SD雄性大鼠50只,随机分为6组:(1)常氧对照组(NC),(2)常氧低强度运动组(NEL),(3)常氧高强度运动组(NEH),(4)低氧对照组(HC),(5)低氧低强度运动组(HEL),(6)低氧高强度运动组(HEH)。低氧组每日20时至次日8时置于低氧舱中,其余时间置于常氧环境下。低氧舱氧浓度控制在14.7%,相当于海拔高度大约2800米。运动组每天在常氧环境中进行30分钟跑台训练,速度定为26.8米/分钟,低强度运动组坡度0度,高强度运动组坡度15度。9周后各组大鼠于安静状态进行宰杀,取股四头肌,匀浆进行NO含量和NOS活性检测。结果显示:常氧高强度运动组股四头肌NO水平与常氧对照组相比呈升高趋势并接近显著性水平(p=0.052)。低氧低运动强度组NO显著高于其他组,NOS变化组间比较均未达显著性水平。说明常氧条件下,高强度运动强度才能使NO释放增加。而在间歇性缺氧条件下,较低强度运动即可使NO释放明显增加。提示间歇性缺氧条件可使引起NO释放的运动强度阈值下降。  相似文献   

Influence of Arm Position and Lung Volume on the Center of Buoyancy of Competitive Swimmers     

Scott P. McLean  Richard N. Hinrichs 《Research quarterly for exercise and sport》2013,84(2):182-189

Purpose: The purpose of this study was to determine if anaerobic performance as measured by the Wingate is decremented in elite female athletes when fraction of inspired oxygen is decreased from 20.9% to 10%. Method: Nine collegiate female soccer players (M_weight = 63.2 ± 10 kg, M_height = 164 ± 4.7 cm, M_age = 18.6 ± 0.5 year) performed 1 Wingate test under each condition separated by at least 24 hr. Oxygen consumption was measured breath by breath using a Sensor-Medics metabolic cart. Postexercise blood lactates were measured using the finger-stick method. During normoxic and hypoxic (10% inspired oxygen [O₂]) conditions, participants inhaled air from a 300-L weather balloon during the 30-s test. Results: Peak power, minimum power, average power, postexercise blood lactate, preexercise and postexercise blood O₂ saturation, and total O₂ consumed during exercise and during recovery were not statistically different between conditions. However, the Fatigue Index and peak ventilation were significantly greater during hypoxia than normoxia (35 ± 11% vs. 27 ± 9% &; 91.6 ± 14.2 L/min vs. 75.2 ± 11.1 L/min, respectively, p < .05, Cohen's d = ? 0.80 and ? 1.29, respectively). Ventilation was elevated during hypoxia within 5 s of beginning the Wingate and remained elevated throughout exercise. This increased ventilation was sufficient to maintain oxygen consumption during exercise. Conclusion: Under hypoxic conditions, the ventilatory response to the Wingate test is perhaps more important than aerobic capacity per se in determining whether or not Wingate performance is decremented.  相似文献   

Effects of periodic carbohydrate ingestion on endurance and cognitive performances during a 40-km cycling time-trial under normobaric hypoxia in well-trained triathletes     

Yi-Hung Liao  Toby Mündel  Yan-Ting Yang  Chen-Chan Wei  Shiow-Chwen Tsai 《Journal of sports sciences》2019,37(16):1805-1815

The purpose of this study was to examine CHO ingestion on a cognitive task using a field-simulated time-trial (TT) under hypoxia in well-trained triathletes. Ten male triathletes (age: 22.1 ± 1.1 years; VO₂max: 59.4 ± 1.4 ml/kg/min) participated in this double-blind/crossover/counter-balanced design study. Participants completed 3 TT trials: 1) normoxic placebo (NPLA; FiO₂ = 20.9%), 2) hypoxic placebo (HPLA; FiO₂ = 16.3%), and 3) hypoxic CHO (HCHO; 6% CHO provided as 2 ml/kg/15 min; FiO₂ = 16.3%). During the TT, physiological responses (SpO₂, HR, RPE, and blood glucose/lactate), cognitive performance, and cerebral haemodynamics were measured. Hypoxia reduced TT performance by ~3.5–4% (p < 0.05), but CHO did not affect TT performance under hypoxia. For the cognitive task, CHO slightly preserved exercise-induced cognitive reaction speed but did not affect response accuracy during hypoxic exercise. However, CHO did not preserve the decreased Hb-Diff (cerebral blood flow, CBF) and increased HHb in the prefrontal lobe (p < 0.05) during hypoxic exercise, and CHO failed to preserve hypoxia-suppressed prefrontal CBF and tissue oxygen saturation. In conclusion, the present study demonstrates that CHO is effective in sustaining reaction speed for a cognitive task but not promoting TT performance during hypoxic exercise, which would be important for strategy-/decision-making when athletes compete at moderate high-altitude.  相似文献   

间歇性低氧训练对大鼠血气分析指标影响的实验研究     

叶鸣  雷志平  姜涛 《西安体育学院学报》2005,22(6):58-61

目的是通过实验对大鼠血气分析指标进行测试,进一步研究间歇性低氧训练对有氧代谢能力和酸碱平衡代谢作用的机理。选用健康纯种SD雄性大鼠40只,随机分为4组:对照组、低氧组、运动组、运动低氧组。NS组自由活动和摄食;HS组进行间歇性低氧训练;NT组进行无负重自由游泳训练;HT组每天先进行运动训练,然后进行间歇性低氧训练,运动和低氧训练的方式和负荷安排同NT组和HS组。3周正式训练后测试并比较各组血气指标。结果表明HS组动脉-静脉O2cont差值比NS升高,具有显著性差异,HT组比NS增大,具有非常显著性差异(P<0.01)。各组动脉-静脉SO2差值的变化与O2cont一致。HT组静脉pH、BB、SB、BE均比NS升高,具有显著性差异。结论为间歇性低氧训练可通过增加组织摄取、利用氧的能力来提高有氧代谢能力;间歇性低氧训练与运动训练相结合可增加血液的碱储备和缓冲酸性代谢产物的能力。  相似文献   

The effects of exercise in hypoxic and normoxic conditions on endothelin-1 and arterial compliance     

Giles LV  Warburton DE  Esch BT  Fedoruk MN  Rupert JL  Taunton JE 《Journal of sports sciences》2012,30(3):261-267

The purpose of this study was to determine the effects of short-term normoxic and hypoxic exercise on plasma endothelin-1 and nitric oxide levels, and the relationship of arterial compliance and pulmonary artery pressure to endothelin-1. Seven endurance-trained males completed two incremental and two steady-state exercise tests performed at ventilatory threshold in normoxia and hypoxia (fraction of inspired oxygen = 0.14). Plasma endothelin-1was measured throughout steady-state tests. Arterial compliance using applanation tonometry, plasma nitric oxide and pulmonary artery pressure using Doppler echocardiography were measured before and after exercise. Small arterial compliance and pulmonary artery pressure significantly increased following exercise. There were no main effects of condition or time for plasma endothelin-1and nitric oxide levels. There were no significant relationships between plasma endothelin-1 and arterial compliance or pulmonary artery pressure. In conclusion, mechanisms other than the endothelial system may play a role in the exercise-induced changes in small artery compliance in this study population. Moderate hypoxia and a 30-minute steady-state exercise have limited effects on plasma endothelin-1 in endurance-trained males.  相似文献   

Effect of environmental feedbacks on pacing strategy and affective load during a self-paced 30 min cycling time trial     

Alexandre Abel  Bertrand Baron  Frédéric Grappe  Marc Francaux 《Journal of sports sciences》2019,37(3):291-297

The purpose of this study was to analyze the pacing strategy and its affective consequences during self-paced cycling time trials (TT) performed at different severity of hypoxia. Eight competitive cyclists performed five 30 min self-paced TTs at their best performance in the following conditions: 1) normobaric normoxia (NN_SL); 2) normobaric hypoxia under two simulated altitudes: 2000 m (NH₂₀₀₀) and 3500 m (NH₃₅₀₀) and 3) normobaric hypoxia but the cyclists were deceived and thought to be at sea level for 2000 m (DecNH₂₀₀₀) and 3500 m (DecNH₃₅₀₀). Power Output (PO), oxygen uptake (VO₂), and blood lactate concentration ([La]) were recorded to assess exercise intensity and physiological adaptations. The rate of perceived exertion (RPE) and pleasure were measured with a CR10 Borg scale to evaluate the affective load (AL). PO and VO₂ decreased with the severity of hypoxia but no significantly difference on performance was measured between deceived and real conditions, except for pacing strategy. The started intensity depends on the exercise expectations, but PO was rapidly adjusted with the physiological constraints and the rate of increase of RPE. Finally, AL did not reach maximal values so that the athletes sustained a physiological and emotional reserve to perform a final spurt.  相似文献