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排序方式: 共有714条查询结果,搜索用时 468 毫秒
1.
B. Falk Y. Weinstein R. Dotan D. A. Abramson D. Mann-Segal J. R. Hoffman 《Scandinavian journal of medicine & science in sports》1996,6(5):259-264
Anaerobic power is characterized by a high degree of specificity regarding both the recruited muscles as well as the recruitment pattern. The popular Wingate Anaerobic Test (WAnT) is a cycling test that does not satisfy the need for a running-specific anaerobic test. We describe such a test, using a novel type of a commercially available treadmill (BRL 1800, Gymrol, France). The ergometer is equipped with a torque motor to neutralize the frictional resistance of the treadmill belt, and a hip-belt harness connected to a horizontal rod. Force applied to the harness is monitored by a strain gauge mounted on the rod, while vertical movement is monitored by a potentiometer at the posterior fixed end of the rod. These, in conjunction with the treadmill belt speed, enable the computation of horizontal and vertical power as well as the combined total output. Power is calculated both as 'peak' power (highest 2.5 s segment) and 'mean' power (20 s duration). Preliminary results of young athletes were generally consistent with the expected age-related changes in anaerobic power. Values obtained on the anaerobic treadmill were always higher than the corresponding WAnT values previously obtained in comparable age groups. The higher values were probably due to the larger muscle mass involved and the shorter peak and mean power durations (2.5 and 20 s versus 5 and 30 s in the WAnT, respectively). This test should enable not only running-specific anaerobic power monitoring but also the characterization of the relationship between the horizontal and vertical components of that power. 相似文献
2.
Abdulmassih S. Iskandrian Jeffrey Johnson Tung T. Le Valerie Wasserleben Virginia Cave Jaekyeong Heo 《Journal of nuclear cardiology》1994,1(2):144-149
Background
This study compared the prognostic value of exercise single-photon emission computed tomographic (SPECT) thallium imaging with that of treadmill exercise score in medically treated patients with coronary artery disease (CAD) 相似文献3.
ADEL ISSA SOUSSOU MOHAMED GAMAL HELMY RAMEZ RAOUF GUINDY ENRICO MARIA GRECO 《Pacing and clinical electrophysiology : PACE》1992,15(11):1804-1808
The pocing rate response of a new acceleration driven pulse generator (SWING 100, SORIN BIOMEDICA) was compared with simultaneous normal sinus rhythm (NSR) during two different treadmill exercises. This pacemaker has a gravitational acceleration sensor able to discriminate between physical activities and vibrations. Six healthy volunteers (three male, three female; aged 21.7 ± 4,3 years), with the pacemaker strapped to their right infraclavicular area, performed each test three times with different rise response curve (RRC) each time: fast, normal, and slow. The fall response curve used was the same as the rising one during each test. Pacing rates were recorded using the VEGA analyzer (SORIN BIOMEDICA) and compared with simultaneous NSR recorded by a 7-channel ECG recorder (MINGOGRAF 7, SIEMENS), During all tests immediate (within seconds) rapid increase in pacemaker rate was seen up to about 60 seconds, then a slower increase followed thereafter. The mean correlation between pacing rates and NSR during the Bruce tests were 0.7941 ± 0.10, 0.8562 ± 0.14, and 0.8292 ± 0.07; during the discontinous tests 0.7292 ± 0.16, 0.7233 ± 0.10, and 0.7480 ± 0.11 for fast, normal, and slow RRC, respectively. Each 30 seconds, nonsignificant differences were present between pacing rate and NSR during all the discontinuous tests; similar responses were observed only during the first two stages of Bruce tests after which NSR was significantly higher than pacemaker rates. The speed of rise to upper rate was the main difference between the different programs (fast, normal, and slow). The discontinuous tests showed that the pacemaker responds more to speed than to grade. In conclusion, the Swing pacemaker is easy to use and program, fast, reliable, and is able to mimic the normal sinus behavior especially during discontinuous activities. 相似文献
4.
Yanagiya T Kanehisa H Tachi M Kuno S Fukunaga T 《European journal of applied physiology》2004,92(1-2):33-38
This study determined mechanical power during movements specific to maximal walking and running using a non-motorized treadmill in 38 elderly [69.4 (5.0) years] and 50 young [24.3 (3.4) years] men. The mean mechanical power over a period of time covering six steps, during which the belt velocity peaked and then kept almost plateau, was determined as a performance score in each of maximal walking (WP) and running (RP). In terms of the value relative to body mass, the relative difference between the two age groups was greater for RP (61.7%) than for WP (21.4%) or isometric knee extension (34.1%) and flexion torque (43.8%). In the two groups, WP was significantly (P<0.05) correlated to knee extension (r=0.582 for the elderly and r=0.392 for the young) and flexion torque (r=0.524 for the elderly and r=0.574 for the young). Similarly, RP was also significantly (P<0.05) correlated to knee extension (r=0.627 for the elderly and r=0.478 for the young) and flexion torque (r=0.500 for the elderly and r=0.281 for the young). In these relationships, the WP adjusted statistically by thigh muscle torque was similar in the two age groups. However, the corresponding value for RP was significantly higher in the young than in the elderly. The findings here indicate that: (1) the difference between the young and elderly men in mechanical power is greater during maximal running than maximal walking, and (2) although the thigh muscle torque contributes to the power production during the two maximal exercise modes in the two age groups, the RP is greater in the young than in the elderly regardless of the difference in the thigh muscle torque. 相似文献
5.
平板运动试验不同阶段出现的室性心律失常分析 总被引:1,自引:0,他引:1
刘士珍 《现代电生理学杂志》2004,11(1):9-10,12
目的:通过进行平板运动试验鉴别室性早搏的性质。方法:从所有做平板运动试验的2383例室性心律失常病例中,选出在不同阶段出现室行早搏的217例患者进行分析。结果:经冠状动脉造影证实确定为冠心病的174例,高血压性心脏病合并冠心病12例,X综合症4例,心律失常15例,植物神经功能紊乱12例。174例冠心病患者7例为左主干病变,58例为双支病变,109例为单支病变。结论:平板运动试验对室性心律失常的定性分析具有较高的临床价值。 相似文献
6.
M. A. Christmass B. Dawson C. Goodman P. G. Arthur 《Acta physiologica (Oxford, England)》2001,172(1):39-52
The role of work period duration as the principal factor influencing carbohydrate metabolism during intermittent exercise has been investigated. Fuel oxidation rates and muscle glycogen and free carnitine content were compared between two protocols of sustained intermittent intense exercise with identical treadmill speed and total work duration. In the first experiment subjects (n=6) completed 40 min of intermittent treadmill running involving a work : recovery cycle of 6 : 9 s or 24 : 36 s on separate days. With 24 : 36 s exercise a higher rate of carbohydrate oxidation approached significance (P=0.057), whilst fat oxidation rate was lower (P ≤ 0.01) and plasma lactate concentration higher (P ≤ 0.01). Muscle glycogen was lower post‐exercise with 24 : 36 s (P ≤ 0.05). Muscle free carnitine decreased (P ≤ 0.05), but there was no difference between protocols. In the second experiment a separate group of subjects (n=5) repeated the intermittent exercise protocols with the addition of a 10‐min bout of intense exercise, followed by 43 ± 5 min passive recovery, prior to sustained (40 min) intermittent exercise. For this experiment the difference in fuel use observed previously between 6 : 9 s and 24 : 36 s was abolished. Carbohydrate and fat oxidation, plasma lactate and muscle glycogen levels were similar in 6 : 9 s and 24 : 36 s. When compared with the first experiment, this result was because of reduced carbohydrate oxidation in 24 : 36 s (P ≤ 0.05). There was no difference, and no change, in muscle free carnitine between protocols. A 10‐min bout of intense exercise, followed by 43 ± 5 min of passive recovery, substantially modifies fuel use during subsequent intermittent intense exercise. 相似文献
7.
目的探讨食道心房调搏心负荷试验(TEAP)诊断冠心病的价值,并与活动平板运动试验(TMET)进行对比,同时对冠状动脉病变程度进行评估。方法自1993年5月~1997年10月,80例拟诊冠心病的住院病人同期行TEAP、TMET及CAG检查;以CAG为诊断标准,确诊为CHD者60例,另20例为CAG正常者。CAG均为右股动脉Seldinger法穿刺,JudkinS法进行。TEAP、TMET以心率达到次极限水平,二阶梯运动试验方法记录ECG。结果TEAP诊断CHD的敏感性、特异性为81.67%、90%,并且与CHD患者冠状动脉病变支数呈正相关。其与TMET的敏感性、特异性相比更可靠(P<0.01)。结论食道心房调搏心负荷试验可以作为一种无创伤性、有效、简便的诊断CHD的方法。并可对冠状动脉病变程度进行初略评估。 相似文献
8.
本文详细叙述了美国GP公司TM210运动负荷平板系统由于仪器比较老,而且是在DOS状态下工作,运行程序经常无缘无故出错,经过一段时间的摸索,找到了简单的方法,迅速修复,保证了设备的正常运行。 相似文献
9.
《Sport》2013,29(3):166-171
The European approach of preparticipation screening to prevent sudden cardiac deaths in sports consists of anamnesis, physical examination and ECG. The knowledge of training-related ECG alterations reduces false-positive results. In high performance sports in Germany and some other countries, an exercise ECG is additionally performed. The implementation of the exercise ECG is generally recommended for athletes older than 35 years. Under laboratory conditions, ECG at rest and during exercise can be involved in the performance diagnostics. Measurements of lactate and respiratory parameters during bicycle and treadmill ergometry can be combined with ECG. 相似文献
10.
目的探讨早期卧位踏车训练在下肢重度烧伤患者功能康复中的临床效果。方法2016年10月至2017年12月,下肢重度烧伤患者30例分为对照组和观察组,各15例。对照组采用常规综合康复,观察组此基础上增加早期卧位踏车训练。入院时和住院治疗6周后,采用焦虑自评量表(SAS)、抑郁自评量表(SDS)、疼痛数字评分法(NRS)、Berg平衡量表(BBS)和6分钟步行测试进行评定。结果治疗后,两组SAS、SDS、NRS评分均明显降低(t>3.636,P<0.01),观察组低于对照组(t>2.319,P<0.05);观察组BBS评分和6分钟步行距离高于对照组(t>2.541,P<0.05)。结论早期卧位踏车训练对下肢重度烧伤患者功能恢复有一定促进作用。 相似文献