Heart Rate and Lactate Levels During Weight-Training Exercise in Trained and Untrained Men

In brief: The effects of squatting exercise on heart rate and blood lactate levels were studied in five trained and five untrained men between the ages of 22 and 37. The subjects performed squats (sets of ten repetitions until exhaustion), resting for 2 1/2 minutes between sets. Total positive work was estimated with the following formula: (bar mass + body mass) X vertical displacement X repetitions. Heart rate, lactate, and rating of perceived exertion were measured immediately before exercise, after each set, and five minutes after reaching exhaustion. The trained subjects performed more total work and had higher heart rates and lactate levels at exhaustion than the untrained subjects, though heart rates and lactate levels were lower for trained subjects at a given bar mass or submaximal work load. The findings suggest that weight training may cause adaptations that result in reduced fatigue and/or enhanced recovery.     

无训练年轻女性骑车与跑步的脂肪氧化动力学及最大脂肪氧化研究

目的:比较无训练年轻女性骑车与跑步的脂肪氧化动力学、最大脂肪氧化强度(Fatmax)和最大脂肪氧化率(MFO)的差异。方法:12名无训练年轻女性采用递增负荷模式分别完成自行车测试和跑台测试,测定每级负荷运动过程中机体的气体代谢指标,采用每级负荷后30秒气体代谢数据计算脂肪氧化率,通过3阶数多项式拟合曲线确定脂肪氧化动力曲线及Fatmax和MFO。结果:运动强度和运动方式对脂肪氧化率均有影响。随着运动强度增加,脂肪氧化率呈先增加后减少的变化趋势。骑车的脂肪氧化率在50%~60%VO2max强度阶段呈现相对较高水平(4.48~4.68 mg/min/kg),跑步的脂肪氧化率在50%~65%VO2max强度阶段呈现相对较高水平(6.36~6.67 mg/min/kg)。相同强度跑步运动脂肪氧化率高于骑车运动,最大脂肪氧化强度和最大脂肪氧化率也高于骑车运动(56.51±2.50%VO2max vs 53.18±3.25%VO2max,P<0.05;6.71±1.15 mg/min/kg vs 4.74±1.67 mg/min/kg,P<0.001)。骑车和跑步诱导脂肪氧化率达最大的95%以上强度范围分别为44.86~60.60%VO2max和48.21~65.41%VO2max。结论:相同强度运动,跑步脂肪氧化率高于骑车,且跑步最大脂肪氧化强度和最大脂肪氧化率也高于骑车,提示在对肥胖、糖尿病及与脂肪代谢相关的其他疾病的运动干预中,跑步的干预效果可能优于骑车。     

低压舱5000m高度上健康青年人心功能的观察

为探讨急性高空缺氧时心血管系统的变化规律，应用ＣＦ－Ⅱ型心血管功能检诊仪对８名男性青年进行低压舱５０００ｍ心功能观察。结果发现：脉率、心输出量、心脏指数、心肌耗氧量均为５０００ｍ高度上前１０ｍｉｎ呈增加趋势，１０ｍｉｎ时达最高。冠脉缺血阈值与上述指标相反，１０ｍｉｎ时为最低。     

海拔梯度对健康男性促红细胞生成素的影响

目的:探讨高原慢性缺氧对促红细胞生成素(EPO)的影响。方法:用双抗体夹心ABC—ELISA法对不同海拔高度健康男性血清EPO水平进行测定,同时对受试人群的血氧饱和度(SaO2)、红细胞(RBC)、血红蛋白(Hb)进行测定。结果:随着海拔高度增加,低氧程度加重,血清EPO的水平增加(P<0.01)。结论:高原慢性缺氧可使健康人血清EPO水平增加,而且EPO的水平随海拔高度的增加而增加。     

Cycling with Video Feedback Improves Performance in Untrained,but Not in Trained Women

The objectives of this study were to assess whether exercise performance responses could be altered when subjects were exposed to interactive video feedback and music (VFM), compared to music only feedback (M). Ten women, 5 well-trained (46.4 ± 4.7 ml × kg^-1 × min^-1) and 5 untrained (34.5 ± 5.7 ml × kg^-1 × min^-1) participated in the study. Neither the trained nor the untrained group exhibited significant differences in HR and VO2 between the VFM and M conditions. The trained subjects cycled at similar speeds and for similar distances during the VFM and M conditions, and also cycled at a higher average speed (23.5 ± 2.1 vs. 15.6 ± 3.2 km × h^-1) and further (11.9 ± 1.1 vs. 7.8 ± 1.6 km) than the untrained subjects (p < 0.01). The untrained subjects cycled further and faster in the VFM versus M condition (p < 0.05), and both the average speed (15.6 ± 3.2 vs. 13.9 ± 2.3 km × h^-1) and average distance cycled (7.8 ± 1.6 vs. 7.0 ± 1.2 km) were also improved in the VFM versus M condition (p < 0.05). No group or exercise condition differences were observed for ratings of perceived exertion or psychological performance. We conclude that VFM does not improve cycling performance in trained women, but untrained women cycle faster and further during a 30-min exercise session when exposed to a combination of interactive video and music feedback.     

装甲车行驶训练对动态姿态平衡的影响

目的研究装甲车训练对动态姿态平衡的影响。方法对 56名被试者在装甲车训练前后进行动态姿态平衡测试。结果装甲车训练后被试者的感觉整合测试 (sensoryorganizationtest)状态 1、2和 3的平衡分SOT1 (P <0 .0 5) ,SOT2 (P <0 .0 0 1 )和SOT3(P <0 .0 0 1 )有显著降低 ,状态 4和 6的平衡分SOT4(P <0 .0 0 1 )和SOT6(P <0 .0 0 1 )有显著增加 ;静态本体感觉分SEN1 (SOT2 /SOT1× 1 0 0 ,P <0 .0 1 )有显著降低 ,而视觉SEN2 (SOT4/SOT1× 1 0 0 ,P <0 .0 1 )和动态本体觉SEN5(SOT( 4 + 5+ 6) /SOT( 1 + 2 + 3)× 1 0 0 ,P <0 .0 1 )有显著增加 ;感觉整合测试状态 2和 3的运动策略分STRAT2 (P <0 .0 1 )和STRAT3(P <0 .0 0 1 )有显著降低。结论装甲车行驶训练对动态姿态平衡能力和感觉整合有影响。     

Preparticipation Screening for Sudden Cardiac Death in High School and College Athletes

In brief: Sudden cardiac death in high school and college athletes is uncommon. When it does occur, its most common causes include hypertrophic cardiomyopathy, aortic rupture associated with Marian's syndrome, congenital coronary artery anomalies, and atherosclerotic coronary artery disease. A screening cardiovascular examination may help identify athletes who are at risk for sudden death. Echocardiography can be a useful tool for identifying previously undetected cardiovascular disease in young athletes, However, including it routinely in preparticipation evaluations is financially, logistically, and legally impractical. A brief but thorough screening history and physical examination should identify individuals who would benefit from a more extensive evaluation, which might include an echocardiogram and other tests. The authors discuss typical findings in individuals who should be evaluated further.     

30d头低位卧床对男性牙龈色彩的影响

目的研究头低位卧床模拟失重对健康人牙龈颜色的影响。方法采用﹣6°头低位卧床模拟失重,在5个时间点:卧床前第3天(HDBR-3)、卧床第10天(HDBR 10)、卧床第20天(HDBR 20)、卧床第30天(HDBR 30)和恢复期第3天(HDBR+3)检测游离龈和附着龈的色彩。结果与卧床前相比,男性志愿者牙龈游离龈、附着龈的L*值在卧床第20天、30天显著升高(P<0.05),在卧床第10天、恢复期第3天无显著性差异;游离龈和附着龈的a*和b*值在卧床第20天、30天和恢复期第3天非常显著升高(P<0.01),在卧床第10天无显著性差异。结论失重环境可使人体游离龈、附着龈发生炎症反应。为降低失重对人体口腔软组织的影响,在航天员的日常训练和航天实验过程中应加强口腔组织的卫生防护。     

跑台运动对高脂饮食诱导的肥胖大鼠骨骼肌肌联素表达的影响

目的:观察跑台运动对高脂饮食诱导的肥胖大鼠骨骼肌肌联素(myonectin)表达的影响。方法:5周龄健康雄性SD大鼠随机分成对照组和高脂喂养组,分别进行普通饲料和高脂饲料喂养,12周后筛选肥胖大鼠16只,随机分为高脂安静组和高脂运动组。跑台训练持续10周,每周5次,每次60 min,跑速26 m/min。测定大鼠血脂及血浆自由脂肪酸水平,采用real-time PCR方法测定比目鱼肌、腓肠肌肌联素m RNA表达,比目鱼肌脂肪酸转位酶(fatty acid translocase,FAT/CD36)的m RNA表达。结果:与对照组相比,高脂饮食喂养大鼠体重和体脂显著增加(P<0.01),总甘油三酯、总胆固醇和低密度脂蛋白水平显著升高,高密度脂蛋白水平显著降低(P<0.05),血自由脂肪酸(free fatty acid,FFA)水平显著升高(P<0.05)。比目鱼肌和腓肠肌肌联素m RNA表达水平显著升高(P<0.05),比目鱼肌CD36表达显著上调(P<0.05)。与高脂饮食组大鼠相比,10周跑台运动大鼠体重显著降低(P<0.01),血脂改善,血FFA水平显著降低(P<0.05)。此外,比目鱼肌和腓肠肌肌联素m RNA表达显著下调(P<0.05),比目鱼肌CD36表达显著降低(P<0.05)。相关性分析发现,骨骼肌肌联素水平与血脂和血糖水平呈显著正相关(P<0.05)。结论:骨骼肌肌联素的表达与血脂、血糖水平显著相关,运动促进了血脂和血糖水平的降低,进而间接下调了骨骼肌肌联素的表达,提示肌联素可能不参与运动引起的自由脂肪酸水平的降低。     

Offloading Effects on Impact Forces and Patellofemoral Joint Loading During Running in Females

BackgroundStructure-specific loading is being increasingly recognized as playing a role in running related injuries. The use of interventions targeted at reducing patellofemoral joint loads have shown effectiveness in reducing symptoms of patellofemoral pain. Use of bodyweight support (BWS) has the potential to reduce loading on the patellofemoral joint during running to augment rehabilitation efforts.Research Question:How is patellofemoral joint loading different when using a harness-based BWS system during running?MethodsTwenty-five healthy females free from lower extremity injury were included. Participants completed four running trials on an instrumented treadmill with varying amounts of BWS using a commercially available harness system. Kinematic data from a 3D motion capture system and kinetic data from the treadmill were combined in a computer model to estimate measures of patellofemoral joint loading, knee kinematics, ground reaction force, and stride frequency.ResultsPeak patellofemoral joint stress and time-integral were reduced when running under BWS conditions compared to control conditions. Incremental decreases in patellofemoral loading were not observed with incremental increases in BWS. Peak knee flexion angle was reduced in all BWS conditions compared to control but was not different between BWS conditions. Knee flexion excursion was reduced in only the high BWS condition. Peak ground reaction force and stride frequency incrementally decreased with increased amounts of BWS.SignificanceHarness-based BWS systems may provide a simple means to reduce patellofemoral joint loading to assist in rehabilitation efforts, such as addressing patellofemoral pain.     

“龙门剑气”对离体蟾蜍心脏搏动干扰的研究

以龙门剑气(外气)施于31以任氏液灌注的离体蟾蜍心脏。结果,其中20例(64.52％)心房和心室搏动停止,26例(83.8％)出现心律不齐。而在32例对照组中停博5例(15.63％),心律不齐8例(25％)。两组间两项结果均有显著性差异(P<0.005)。实验表明龙门剑气对离体蟾蜍心脏搏动有明显的干扰作用。     

Short-Term Effects of Transjugular Intrahepatic Shunt on Cardiac Function Assessed by Cardiac MRI: Preliminary Results

The purpose of this study was to assess short-term effects of transjugular intrahepatic shunt (TIPS) on cardiac function with cardiac magnetic resonance imaging (MRI) in patients with liver cirrhosis. Eleven patients (six males and five females) with intractable esophageal varices or refractory ascites were imaged with MRI at 1.5 T prior to, within 24 h after, and 4–6 months after TIPS creation (n = 5). Invasive pressures were registered during TIPS creation. MRI consisted of a stack of contiguous slices as well as phase contrast images at all four valve planes and perpendicular to the portal vein. Imaging data were analyzed through time-volume curves and first derivatives. The portoatrial pressure gradient decreased from 19.8 ± 2.3 to 6.6 ± 2.3, accompanied by a nearly two fold increase in central pressures and pulmonary capillary wedge pressure immediately after TIPS creation. Left and right end diastolic volumes and stroke volumes increased by 11, 13, and 24%, respectively (p < 0.001), but dropped back to baseline at follow-up. End systolic volumes remained unchanged. E/A ratios remained within normal range. During follow-up the left ventricular mass was larger than baseline values in all patients, with an average increase of 7.9 g (p < 0.001). In conclusion, the increased volume load shunted to the heart after TIPS creation transiently exceeded the preload reserve of the right and left ventricle, leading to significantly increased pulmonary wedge pressures and persistent enlargement of the left and right atria. Normalization of cardiac dimensions was observed after months together with mild left ventricular hypertrophy.     

The Acute and Prolonged Effects of Marathon Running on 20 Blood Parameters

In brief: Abnormal blood chemistry values may be a normal physiological response to marathon running and training. This was shown by elevations in creatine phosphokinase, high density lipoproteins, lactate dehydrogenase, and WBCs after a marathon run. Significant changes(p <.05) were noted in all blood parameters except globulin and high density lipoproteins from subjects before the race to immediately after the race and two to three weeks after the race. Insignificant differences in blood chemistry values were observed in runners with different running speeds, previous marathon experience, age, body weight, and average training miles per week.     

女大学生递增负荷跑步训练期间血红蛋白与红细胞参数相关分析

目的:探讨女大学生运动性血红蛋白低下与红细胞参数的相关关系。方法:随机选取广州体育学院体育教育系女学生15人,进行持续4周、每周5天、起始负荷强度为60%最大心率、每周强度递增10%的跑步训练。训练前及训练过程中每周末测试受试者血红蛋白(Hb)、平均红细胞体积(MCV)、平均红细胞血红蛋白量(MCH)、平均红细胞血红蛋白浓度(MCHC)、网织红细胞计数(Ret)、红细胞体积分布宽度(RDW)、血红蛋白含量分布宽度(HDW)、平均网织红细胞体积(MCVr)、平均网织红细胞血红蛋白浓度(CHCMr)及血清铁(Fe)和铁蛋白(Fer)。结果:经4周递增负荷跑步训练,女大学生Hb呈进行性显著下降(P<0.01),表现为运动性血红蛋白低下,MCV、MCH、MCHC、CHCMr、HDW、血清铁蛋白呈显著或极显著降低(P<0.05,P<0.01);RDW呈显著递增(P<0.05);Ret、血清铁变化无统计学意义(P>0.05)。相关分析发现,血红蛋白浓度与MCHC和CHCMr相关性最大。结论:4周递增负荷跑步训练可诱导体育教育系女大学生产生运动性血红蛋白低下,其变化与MCHC和CHCMr相关性最大,而与血清Fe、RDW、HDW及MCV无明显相关性。     

过度训练对大鼠心肌细胞凋亡的影响

为了研究过度训练对大鼠心肌细胞凋亡的影响 ,通过对大鼠进行力竭性游泳训练建立大鼠过度训练模型 ,用DNA原位末端标记法检测心肌细胞的凋亡 ,并用免疫组化的方法检测心肌细胞中bcl- 2和Fas蛋白的表达情况。结果发现 :①过度训练时 ,大鼠心肌细胞凋亡显著增加。心肌细胞凋亡可能是过度训练影响心血管功能的病理生理机制。②过度训练时 ,大鼠心肌细胞中bcl- 2蛋白的表达显著下降 ,Fas蛋白的表达轻度增加。因此 ,过度训练抑制bcl- 2蛋白的表达而促进Fas蛋白的表达 ,这可能是过度训练时大鼠心肌细胞凋亡发生的基因调控机制。③过度训练时 ,大鼠心肌组织和血清中SOD活性显著下降 ,MDA含量显著增加。因此 ,过度训练时机体抗氧化能力下降 ,导致氧自由基生成增多。这可能也是心肌细胞凋亡的调节机制。     

不同超滤方法用于婴幼儿先心病体外循环手术的围术期比较

目的比较不同超滤方法对于低体重先心病体外循环手术病人围术期的影响。方法回顾性分析我院采用改良超滤前后13例低体重(<15 kg)先心病体外循环手术病人的临床状况,其中常规超滤(CUF)组6例,常规超滤+改良超滤(CUF+MUF)组7例,对比指标包括转流时间;主动脉阻断时间;转流前后的血球压积及血红蛋白,术后引流量,术后呼吸机通气时间,ICU滞留时间,围术期红细胞悬液用量,呋塞米的使用情况。结果体外循环前后Hct、Hb和总细胞悬液用量无统计学差异(P>0.05);手术后呋塞米用量和胸腔引流量CUF+MUF组明显小于CUF组(P<0.05)。结论改良超滤技术可以改善婴幼儿体外循环心脏手术后病人的器官功能及预后。