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《健身科学》2004,(12)
胃要完成如此重要的生理使命,其前提是一定要健康。那么,你的胃健康吗?不妨来一次自测看看。测试方案由12道题组成———1、是否有过胃部反酸感觉A从来没有过0分B每月1-2次4分C每周1-2次8分D每周3-5次12分E每周6次以上16分2、是否有过上腹部疼痛或不适感A从来没有过0分B每月1-2次2分C每周1-2次4分D每周3-5次6分E每周6次以上8分3、有无腹胀现象A从不0分B每月1-2次2分C每周1-2次4分D每周3-5次6分E每周6次以上8分4、是否经常感到心窝部有烧灼不适感A从不0分B每月1-2次4分C每周1-2次8分D每周3-5次12分E每周6次以上16分5、是否有咽喉发炎… 相似文献
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本研究的目的是评价香港优秀壁球运动员的生理及运动专项素质。10名优秀壁球运动员参加了此研究。最大吸氧量（VO2max）测定用连续递增负荷跑台方法，运动专项场地测试在壁球场中进行。测试结果为：身高172．6±4．3cm，作重67．7±6．9kg；体脂7．4±3．4％，用力肺活量（FVC）5．13±0．26升；VO2max61．7±3．4ml·kg-1·min-1，无氧阈（AT）80．2±3．3％VO2max；非乳酸能15．5±1．8W·kg-1，乳酸功323．5±29．4J·kg-1。结果表明，香港壁球运动员具有相当高的心肺运动专项素质。这也是他们取得亚洲冠军的成功因素之一 相似文献
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短期高强度训练对优秀篮球运动员有氧耐力的影响 总被引：7，自引：1，他引：6
为了调查短期高强度训练对篮球运动员有氧耐力的影响 ,对 2 0名 (男、女各 10名 )优秀篮球运动员 ,进行跑台渐增负荷运动直到力竭为止。同时测定气体代谢最大吸氧量 (VO2max)、通气量 (VE)、血乳酸(BLa)、心率 (HR)、血睾酮 (T)、皮质醇 (Cor)及血红蛋白 (Hb)。结果为 :1)短期高强度训练期后男、女两组无氧阈 (AT)值与训练前相比较均有显著性差异 (P <0 .0 5 ) ,但VO2max却未有显著性差异 ;2 )短期高强度训练期后男、女两组Hb值与训练前相比较均有显著性差异 (P <0 .0 5 ) ,而T、Cor在训练期前后却未有显著性差异。其结果表明 ,短期高强度训练并不能提高VO2max,而AT却明显提高。提示可采用AT值作为反映篮球运动员有氧耐力的指标。 相似文献
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目的：拟探讨核呼吸因子1（NRF1）基因多态性与最大（VO2max）和次最大有氧能力（running economy，RE）的关联性。方法：102名无训练史的健康男子进行18周有氧耐力训练，测试训练前后的VO2 max和12km／h跑速下的RE。用FCR-RFLP分析NRF1基因的SNPrs2302970、rs6949152和rs10500120多态性。结果：3个多态位点均符合H—W平衡（P〉0．05）。rs2302970与rs6949152强连锁不平衡（D’=0．950，12=0．631），经haplo．em推算，主要存在4种单体型；3个SNPs及单体型与VO2max的初始值及训练敏感性均不关联；RE的初始能力与rs2302970多态性关联，携带CT基因型的群体显著高于CC基因型。RE的训练敏感性与rs2302970和rs6949152多态性关联，携带CT或AG基因型的群体显著高于CC或AA基因型。结论：NRF1基因多态性能够预测中国北方地区汉族男性次最大有氧能力的差异。 相似文献
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HiHiLo对优秀男子中跑运动员有氧运动能力的影响 总被引：1，自引：0，他引：1
通过对8名优秀中跑运动员27天HiHiLo训练前、后与运动能力相关指标进行分析，观察其变化规律，以期为该方法在速耐型运动员中的应用提供理论和实验依据。方法：8名男性受试者每天在低氧环境中（14．2％～14．8％O2）暴露大于10h，每周低氧环境下（15．4％02）以90％VO2max强度进行功率自行车训练3次，每次5min，共4组，组间间隔2min，同时每天完成常氧环境下的专项训练课。测定27天训练前、后的VO2max和训练前、训练1周后、训练2周后、训练3周后、停训后第5天的血象指标。结果：训练后VO2max显著增加达13．65％（P〈0．05）；RBC、HCT在第2周开始出现显著性下降（P〈0．05），第3周继续出现非常显著性降低（P〈0．01），随后开始回升，至低氧暴露结束第5天时与训练前无显著性差异；Hb在1周后出现显著性上升（P〈0．05），而后下降，在第3周出现非常显著性差异（P〈0．01），随后又上升，低氧暴露结束后第5天显著性升高（P〈0．05）。结论：HiHi-Lo训练方法可以增加优秀中跑运动员的VO2max和Hb含量，从而有助于提高有氧能力。 相似文献
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上海汉族优秀耐力运动员ACE基因I/D多态性与最大有氧能力(VO2max)的关联研究 总被引：9，自引：2，他引：7
采用PCR和breath by breath方法，对上海汉族55名优秀游泳运动员、60名优秀赛艇运动员和85名汉族普通人的ACE基因I／D多态性和VO2max进行检测。结果显示：1）上海汉族优秀游泳和赛艇运动员ACE基因的基因型和等位基因频率与上海和成都地区汉族普通人组无明显差异（P〉0．05）；与Caucasian人群相比，均存在非常显著性差异（P〈0．0001），表现出明显的民族和地区的差异性；游泳和赛艇项目健将和一级运动员间的基因型和等位基因频率分布，存在明显差异（P〈0．05）；游泳运动员水平越高，Ⅱ型所占比例就越高，赛艇运动员中水平越高，ID型的比例越大；2）不同基因型的游泳运动员的VO2max、VO2max／kg、VCO2max、VEmax、O2-plusemax、Wmax和Tmax等指标，均表现为Ⅱ型〉DD型〉ID型，Ⅱ型明显优于ID型（P〈0．05～0．01），而赛艇运动员则表现为ID型〉Ⅱ型〉DD型，ID明显优于DD型（P〈0．05～0．01）。结果提示，游泳项目中具有Ⅱ基因型或Ⅰ等位基因的运动员，赛艇项目中具有ID基因型或Ⅰ等位基因的运动员，可能属于运动训练敏感的高反应群体，经过多年系统科学的训练，具有成为优秀运动员的可能。ACE基因I／D多态性可作为运动训练和选材中高敏感的、非常重要的遗传标记之一。 相似文献
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目的：探讨不同强度运动对青春期肥胖大鼠肝肾功能的影响。方法：建模7周后,选取喂食高脂饲料的肥胖大鼠24只,随机分为4组,每组6只,分别为安静对照组（Oc）、低强度运动组（OL）、中强度运动组（OM）、高强度运动组（OH）。OL、OM、oH分别以15-18m／min、21-25m／min和28-32m／min的强度运动,坡度均为0。,lh／天,5次／周,共干预8周。干预后麻醉大鼠采集血液,测定血浆蛋白以及肝肾功能相关指标。结果：8周运动干预后,大鼠体重、内脏脂肪量及体脂率运动组较对照组显著降低（P〈O．01）;内脏脂肪量及体脂率0M、0H组显著低于OL组（P〈O．05、P〈O．01）;血白蛋白OH组高于0c组（P〈0．01）。血尿素氮与血肌酐各组之间无明显差异（P〉o．05）。结论：实施8周不同强度运动干预后,使青春期肥胖大鼠体重、内脏脂肪量和体脂率明显降低,随着运动强度的增加,调节效果更明显。该运动干预能有效调节血浆蛋白与肝肾功能,但不同运动强度之间无明显差别。 相似文献
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目的：探讨大鼠海马CAl区微注射L-精氨酸（L—Arg）对大鼠空间学习记忆的影响。进而了解L—Arg的作用和机理,为深入研究该药物的神经生物学机制提供实验依据。方法：10只SD大鼠随机分为实验组（n=5,微量注射L—Arg0．5μl,浓度为50g／L）和对照组（n：5,微量注射生理盐水0．5μl）,利用八臂迷宫对大鼠进行测试,记录不同药物注射下大鼠在八臂迷宫中的工作记忆错误和参考记忆错误。结果：大鼠海马区微注射生理盐水前后八臂迷宫实验3--作记忆错误分别为2±0．3次、2．4±0．2次,前后无显著变化（P〉0．05）;注药前后参考记忆错误分别为6．2±0．3次、6．4±0．2次,前后无显著变化（p〉0．05）。实验测量结果对比发现,导管植入手术对大鼠空间学习记忆能力无明显影响;大鼠海马区微注射L-Arg前后测试时间分别为224．1s、223．8s,注射前后无明显差异（P〉0．05）。大鼠海马区注射L—Arg后工作记忆错误为1．9±0．3次,对照组为2．7±0．4次,实验组工作记忆错误次数明显降低（P〈0．05）;注药后参考记忆错误分别为实验组5．3±0．4次、对照组6．5±0．5次,实验组参考记忆错误次数明显降低（P〈0．05）。结论：海马区微注射生理盐水对大鼠的学习记忆能力影响不大,海马区微注射L—Arg能提高大鼠的学习记忆能力。 相似文献
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The aims of this study were two-fold: (1) to consider the criterion-related validity of the multi-stage fitness test (MSFT) by comparing the predicted maximal oxygen uptake (.VO(2max)) and distance travelled with peak oxygen uptake (VO(2peak)) measured using a wheelchair ergometer (n = 24); and (2) to assess the reliability of the MSFT in a sub-sample of wheelchair athletes (n = 10) measured on two occasions. Twenty-four trained male wheelchair basketball players (mean age 29 years, s = 6) took part in the study. All participants performed a continuous incremental wheelchair ergometer test to volitional exhaustion to determine .VO(2peak), and the MSFT on an indoor wooden basketball court. Mean ergometer .VO(2peak) was 2.66 litres . min(-1) (s = 0.49) and peak heart rate was 188 beats . min(-1) (s = 10). The group mean MSFT distance travelled was 2056 m (s = 272) and mean peak heart rate was 186 beats . min(-1) (s = 11). Low to moderate correlations (rho = 0.39 to 0.58; 95% confidence interval [CI]: -0.02 to 0.69 and 0.23 to 0.80) were found between distance travelled in the MSFT and different expressions of wheelchair ergometer .VO(2peak). There was a mean bias of -1.9 beats . min(-1) (95% CI: -5.9 to 2.0) and standard error of measurement of 6.6 beats . min(-1) (95% CI: 5.4 to 8.8) between the ergometer and MSFT peak heart rates. A similar comparison of ergometer and predicted MSFT .VO(2peak) values revealed a large mean systematic bias of 15.3 ml . kg(-1) . min(-1) (95% CI: 13.2 to 17.4) and standard error of measurement of 3.5 ml . kg(-1) . min(-1) (95% CI: 2.8 to 4.6). Small standard errors of measurement for MSFT distance travelled (86 m; 95% CI: 59 to 157) and MSFT peak heart rate (2.4 beats . min(-1); 95% CI: 1.7 to 4.5) suggest that these variables can be measured reliably. The results suggest that the multi-stage fitness test provides reliable data with this population, but does not fully reflect the aerobic capacity of wheelchair athletes directly. 相似文献
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运用Matsumoto测定EMGFT的方法对青少年足球运动员EMGFT进行测试,目的在于验证肌电阈稳定性;检验EMGFT与LAT、VAT、HRT的相关性;探讨EMGFT无损伤测定无氧阈方法的可行性。方法:递增负荷实验确定LAT、VAT、HRT;肌电阈实验确定EMGFT。结果:EMGFT稳定性实验,两次均值分别为151.08±10.52 W、153.56±12.93 W,r=0.95(P<0.001),组间无显著性差异(P>0.05);以VO2为参数,EMGFT、LAT、VAT、HRT均值分别为2481±463ml/min、2507±501ml/min、2580±474ml/min、2610±517ml/min,EMGFT分别与LAT、VAT、HRT相关性检验r=0.97(P<0.001)、r=0.91(P<0.001)、r=0.76(P<0.05),配对样本t检验P>0.05、P>0.05、P<0.05;以功率为参数,EMGFT、LAT、VAT、HRT均值分别为157±20 W、158±20 W、162±21 W、162±26 W,相关性检验r=0.96(P<0.001)、r=0.93(P<0.001)、r=0.71(P<0.05),配对样本t检验P>0.05、P>0.05、P<0.05。结论:应用Matsumoto肌电无氧阈方法能很好地确定EMGFT,稳定性较好;EMGFT与LAT、VAT呈高度相关,出现时间顺序依次为EMGFT→LAT→VAT,EMGFT略早于LAT和VAT,呈一定的规律性,表明EMGFT可以用于检测无氧阈,具有无损伤、简单、易测等优点;HRT检测无氧阈不稳定,说明HRT不宜作为无氧阈的评定指标。 相似文献
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In this study, we tested the hypothesis that elite dinghy sailing is a whole-body, dynamic, repeated-effort sport, and that increased heart rate and oxygen consumption reflect its dynamic element. Six elite male Laser sailors (mean age 19.7 years, s = 1.82; height 1.81 m, s = 0.03; body mass 78.0 kg, s = 4.1) performed a cycle ergometer test to volitional exhaustion to determine peak oxygen uptake (VO(2peak)) and a simulated 30-min upwind leg sail on a specially constructed Laser sailing ergometer. The simulation protocol was based on video analysis of previous Laser World Championships. Expired gases were collected in Douglas bags, heart rate recorded at rest and after every 5 min, and pre- and post-simulation capillary blood samples taken for blood lactate analysis. Results were analysed with a one-way analysis of variance. Mean VO(2peak) was 4.32 l . min(-1) (s = 0.16). Mean simulation VO(2) was 2.51 l . min(-1) (s = 0.24) and peaked at 2.58 l . min(-1) (s = 0.25) during the 5th minute. Mean simulation heart rate was 156 beats . min(-1) (s = 8), peaking during the final minute at 160 beats . min(-1) (s = 10). These results suggest that, unlike pseudo-isometric static hiking, elite dinghy sailing demands a substantial proportion (58%VO(2peak), s = 5.6) of aerobic capacity. 相似文献
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In this study, we examined thermoregulatory responses to ingestion of separate aliquots of drinks at different temperatures during low-intensity exercise in conditions of moderate heat stress. Eight men cycled at 50% (s = 3) of their peak oxygen uptake (VO2peak) for 90 min (dry bulb temperature: 25.3 degrees C, s = 0.5; relative humidity: 60%, s = 5). Four 400-ml aliquots of flavoured water at 10 degrees C (cold), 37 degrees C (warm) or 50 degrees C (hot) were ingested after 30, 45, 60, and 75 min of exercise. Immediately after the 90 min of exercise, participants cycled at 95% VO2peak to exhaustion to assess exercise capacity. There were no differences between trials in rectal temperature at the end of the 90 min of exercise (cold: 38.11 degrees C, s = 0.30; warm: 38.10 degrees C, s = 0.33; hot: 38.21 degrees C, s = 0.30; P = 0.765). Mean skin temperature between 30 and 90 min tended to be influenced by drink temperature (cold: 34.49 degrees C, s = 0.64; warm: 34.53 degrees C, s = 0.69; hot: 34.71 degrees C, s = 0.48; P = 0.091). Mean heart rate from 30 to 90 min was higher in the hot trial (129 beats . min(-1), s = 7; P < 0.05) than on the cold (124 beats . min(-1), s = 9) and warm trials (126 beats . min(-1), s = 8). Ratings of thermal sensation were higher on the hot trial than on the cold trial at 35 and 50 min (P < 0.05). Exercise capacity was similar between trials (P = 0.963). The heat load and debt induced by periodic drinking resulted in similar body temperatures during low-intensity exercise in conditions of moderate heat stress due to appropriate thermoregulatory reflexes. 相似文献
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Nine males cycled at 53% (s = 2) of their peak oxygen uptake (VO(2peak)) for 90 min (dry bulb temperature: 25.4 degrees C, s = 0.2; relative humidity: 61%, s = 3). One litre of flavoured water at 10 (cold), 37 (warm) or 50 degrees C (hot) was ingested 30 - 40 min into exercise. Immediately after the 90 min of exercise, participants cycled at 95%VO(2peak) to exhaustion to assess exercise capacity. Rectal and mean skin temperatures and heart rate were recorded. The gradient of rise in rectal temperature was influenced (P < 0.01) by drink temperature. Mean skin temperature was highest in the hot trial (cold trial: 34.2 degrees C, s = 0.5; warm trial: 34.4 degrees C, s = 0.5; hot trial: 34.7 degrees C, s = 0.6; P < 0.01). Significant differences were observed in heart rate (cold trial: 132 beats . min(-1), s = 13; warm trial: 134 beats . min(-1), s = 12; hot trial: 139 beats . min(-1), s = 13; P < 0.05). Exercise capacity was similar between trials (cold trial: 234 s, s = 69; warm trial: 214 s, s = 52; hot trial: 203 s, s = 53; P = 0.562). The heat load and debt induced via drinking resulted in appropriate thermoregulatory reflexes during exercise leading to an observed heat content difference of only 33 kJ instead of the predicted 167 kJ between the cold and hot trials. These results suggest that there may be a role for drink temperature in influencing thermoregulation during exercise. 相似文献
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Following preliminary indications that in some individuals arm exercise enhanced rather than reduced simultaneous leg endurance, ten young men and women performed three forms of intermittent work to volitional exhaustion, under duty cycles of 45 s work, 15 s rest. The protocols were as follows: (A) knee extensions at 30% maximum voluntary contraction (MVC); (B) 30% MVC knee extensions combined with arm cranking at 130% of their own lactate threshold; (C) combined 30% MVC knee extensions and arm cranking at 20% of their own lactate threshold. Heart rate, oxygen uptake (VO(2)), and blood lactate concentration were among the variables recorded throughout. All physiological indicators of demand were substantially higher in protocol B than in protocols A or C [heart rate: (A) 154 beats . min(-1), (B) 171 beats . min(-1), (C) 150 beats . min(-1); VO(2): (A) 11.9 ml . kg(-1) . min(-1), (B) 21.7 ml . kg(-1) . min(-1), (C) 14.2 ml . kg(-1) . min(-1); blood lactate concentration: (A) 3.3 mmol . l(-1), (B) 5.1 mmol . l(-1), (C) 2.8 mmol . l(-1)], yet there were no significant differences (P > 0.05) in the endurance times between the three conditions [(A) 11.43 min, (B) 11.1 min, (C) 10.57 min] and seven participants endured longest in protocol B. Results from protocol (C) cast doubt on explanations in terms of psychological distraction. We suggest that lactic acid produced by the arms is shuttled to the legs and acts there either as a supplementary fuel source or as an antagonist to the depressing effects of increased potassium concentration. 相似文献
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The referee has responsibility for control of players' behaviour during competitive football and implementing the rules of the game. To do this, the referee and the two assistant referees are obliged to keep up with play. Referees cover 10,000 m on average during a game, mean heart rate is about 160 - 165 beats . min(-1) and oxygen uptake is close to 80% of maximum (VO(2max). Assistant referees cover approximately 7500 m, mean heart rate is about 140 beats . min(-1) and the corresponding oxygen uptake is 65% VO(2max). Both groups display evidence of fatigue towards the end of the game, a phenomenon that has not been thoroughly examined for nutritional interventions. The estimated energy expenditure of referees during a game exceeds 5600 kJ. Both referees and assistant referees execute unorthodox patterns of movement during match-play that increase energy expenditure over normal locomotion. As high standards of fitness and decision making are expected of professional referees, there are nutritional consequences associated with the training regimes they adopt. The effects of nutritional interventions on cognitive performance during the later stages of a game are in need of further investigation. 相似文献
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The aim of this study was to quantify the physiological loads of programmed "pre-season" and "in-season" training in professional soccer players. Data for players during each period were included for analysis (pre-season, n = 12; in-season, n = 10). We monitored physiological loading of training by measuring heart rate and rating of perceived exertion (RPE). Training loads were calculated by multiplying RPE score by the duration of training sessions. Each session was sub-categorized as physical, technical/tactical, physical and technical/tactical training. Average physiological loads in pre-season (heart rate 124 ± 7 beats · min(-1); training load 4343 ± 329 Borg scale · min) were higher compared with in-season (heart rate 112 ± 7 beats · min(-1); training load 1703 ± 173 Borg scale · min) (P < 0.05) and there was a greater proportion of time spent in 80-100% maximum heart rate zones (18 ± 2 vs. 5 ± 2%; P < 0.05). Such differences appear attributable to the higher intensities in technical/tactical sessions during pre-season (pre-season: heart rate 137 ± 8 beats · min(-1); training load 321 ± 23 Borg scale · min; in-season: heart rate 114 ± 9 beats · min(-1); training load 174 ± 27 Borg scale · min; P < 0.05). These findings demonstrate that pre-season training is more intense than in-season training. Such data indicate that these adjustments in load are a direct attempt to deliver training to promote specific training adaptations. 相似文献
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Relationship between laboratory-measured variables and heart rate during an ultra-endurance triathlon 总被引：1，自引：1，他引：0
Laursen PB Knez WL Shing CM Langill RH Rhodes EC Jenkins DG 《Journal of sports sciences》2005,23(10):1111-1120
The aim of the present study was to examine the relationship between the performance heart rate during an ultra-endurance triathlon and the heart rate corresponding to several demarcation points measured during laboratory-based progressive cycle ergometry and treadmill running. Less than one month before an ultra-endurance triathlon, 21 well-trained ultra-endurance triathletes (mean +/- s: age 35 +/- 6 years, height 1.77 +/- 0.05 m, mass 74.0 +/- 6.9 kg, = 4.75 +/- 0.42 l x min(-1)) performed progressive exercise tests of cycle ergometry and treadmill running for the determination of peak oxygen uptake (VO2peak), heart rate corresponding to the first and second ventilatory thresholds, as well as the heart rate deflection point. Portable telemetry units recorded heart rate at 60 s increments throughout the ultra-endurance triathlon. Heart rate during the cycle and run phases of the ultra-endurance triathlon (148 +/- 9 and 143 +/- 13 beats x min(-1) respectively) were significantly (P < 0.05) less than the second ventilatory thresholds (160 +/- 13 and 165 +/- 14 beats x min(-1) respectively) and heart rate deflection points (170 +/- 13 and 179 +/- 9 beats x min(-1) respectively). However, mean heart rate during the cycle and run phases of the ultra-endurance triathlon were significantly related to (r = 0.76 and 0.66; P < 0.01), and not significantly different from, the first ventilatory thresholds (146 +/- 12 and 148 +/- 15 beats x min(-1) respectively). Furthermore, the difference between heart rate during the cycle phase of the ultra-endurance triathlon and heart rate at the first ventilatory threshold was related to marathon run time (r = 0.61; P < 0.01) and overall ultra-endurance triathlon time (r = 0.45; P < 0.05). The results suggest that triathletes perform the cycle and run phases of the ultra-endurance triathlon at an exercise intensity near their first ventilatory threshold. 相似文献
20.
Determinants of success during triathlon competition 总被引：1，自引：0，他引：1
D R Dengel M G Flynn D L Costill J P Kirwan 《Research quarterly for exercise and sport》1989,60(3):234-238
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