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1.
The purpose of the present study was to assess fitness and running performance in a group of recreational runners (men, n = 18; women, n = 13). 'Fitness' was determined on the basis of their physiological and metabolic responses during maximal and submaximal exercise. There were strong correlations between VO2 max and treadmill running speeds equivalent to blood lactate concentrations of 2 mmol l-1 (V-2 mM) or 4 mmol l-1 (V-4 mM), 'relative running economy' and 5 km times (r = -0.84), but modest and non-significant correlations between muscle fibre composition and running performance. The results of the submaximal exercise tests suggested that the female runners were as well trained as the male runners. However, the men still recorded faster 5 km times (19.20 +/- 1.97 min vs 20.97 +/- 1.70 min; P less than 0.05). Therefore the of the present study suggest that the faster performance times recorded by the men were best explained by their higher VO2 max values, rather than their training status per se.  相似文献   

2.
The purpose of the study was to relate three determinants of distance running success, (a) maximal oxygen consumption (VO2max), (b) ventilatory threshold (VT), and (c) running economy (RE), to actual running time in a 5-km race (ART). Twenty-four female runners (M age = 15.9 years) from four high school teams that competed at the Massachusetts All-State 5-km Cross Country Championship Meet and placed 1st, 7th, 19th, and 20th were tested in the laboratory. The mean VO2max of these runners was 61.7 ml.kg-1.min-1, HRmax 201 b.min-1, VEmax 100 L.min-1, and RER 1.10. The VT occurred at 79% of the VO2max, and HR of 184 b.min-1 (92% of HRmax). The velocity at VT (vVT) and velocity at VO2max (vVO2max) was correlated with ART, r(22) = .78 and .77 (p less than .001), respectively. The VO2 at VT and at maximal exercise was correlated with ART by r(22) = -.66 and -.69 (p less than .001), respectively. The VO2 at 215 m.min-1 (8 mph) was poorly related to ART, r(22) = -.05, p greater than .05. It was concluded that either of the derived variables vVT and vVO2max appear to explain significant variation in distance running performance among adolescent female cross country runners.  相似文献   

3.
Differences in gender and performance in off-road triathlon   总被引:1,自引:1,他引:0  
The aims of this study were: (1) to examine performance trends and compare elite male and female athletes at the off-road triathlon (1.5-km swim, 30-km mountain biking, and 11-km trail running) world championships since its inception in 1996, and (2) to compare gender-related differences between off-road triathlon and conventional road-based triathlon. Linear regression analyses and ANOVA were used to examine performance trends and differences between the sexes. Elite male performance times stabilized over the 2005-2009 period, whereas elite female performance times continued to improve, especially for the run leg. Differences in performance times between the sexes were less marked in swimming than in mountain biking and running, whereas differences in power output were more marked for mountain biking than for swimming and running. In addition, differences in cycling between the sexes were greater for off-road than conventional on-road triathlon. The specific aspects of mountain biking (e.g. level and terrain) may partly explain the significant differences between the sexes recorded in cycling for off-road triathlon. Future studies will need to focus on the physiological bases of off-road triathlon and how they differ from conventional triathlon.  相似文献   

4.
It is common for the physiological working capacity of a triathlete when cycling and running to be assessed on two separate days. The aim of this study was to establish whether an incremental running test to exhaustion has a negative effect after a 5 h recovery from an incremental cycling test. Eight moderately trained triathletes (age, 26.2 +/- 3.4 years; body mass, 67.3 +/- 9.1 kg; VO2max when cycling, 59 +/- 13 ml x kg x min(-1); mean +/- s) completed an incremental running test 5 h after an incremental cycling test (fatigue) as well as an incremental running test without previous activity (control). Maximum running speed, maximal oxygen uptake (VO2max) and the lactate threshold were determined for each incremental running test and correlated with the average speed during a 5 km run, which was performed immediately after a 20 km cycling time-trial, as in a sprint triathlon. There were no significant differences in maximum running speed, VO2max or the lactate threshold in either incremental running test (control or fatigue). Furthermore, good agreement was found for each physiological variable in both the control and fatigue tests. For the fatigue test, there were significant correlations between the average speed during a 5 km run and both VO2max expressed in absolute terms (r = 0.83) and the lactate threshold (r = 0.88). However, maximum running speed correlated most strongly with the average speed during a 5 km run (r = 0.96). The results of this study indicate that, under controlled conditions, an incremental running test can be performed successfully 5 h after an incremental cycling test to exhaustion. Also, the maximum running speed achieved during an incremental running test is the variable that correlates most strongly with the average running speed during a 5 km run after a 20 km cycling time-trial in well-trained triathletes.  相似文献   

5.
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   

6.
Endurance running performance in athletes with asthma   总被引:1,自引:0,他引:1  
Laboratory assessment was made during maximal and submaximal exercise on 16 endurance trained male runners with asthma (aged 35 +/- 9 years) (mean +/- S.D.). Eleven of these asthmatic athletes had recent performance times over a half-marathon, which were examined in light of the results from the laboratory tests. The maximum oxygen uptake (VO2max) of the group was 61.8 +/- 6.3 ml kg-1 min-1 and the maximum ventilation (VEmax) was 138.7 +/- 24.7 l min-1. These maximum cardio-respiratory responses to exercise were positively correlated to the degree of airflow obstruction, defined as the forced expiratory volume in 1 s (expressed as a percentage of predicted normal). The half-marathon performance times of 11 of the athletes ranged from those of recreational to elite runners (82.4 +/- 8.8 min, range 69-94). Race pace was correlated with VO2max (r = 0.863, P less than 0.01) but the highest correlation was with the running velocity at a blood lactate concentration of 2 mmol l-1 (r = 0.971, P less than 0.01). The asthmatic athletes utilized 82 +/- 4% VO2max during the half-marathon, which was correlated with the %VO2max at 2 mmol l-1 blood lactate (r = 0.817, P less than 0.01). The results of this study suggest that athletes with mild to moderate asthma can possess high VO2max values and can develop a high degree of endurance fitness, as defined by their ability to sustain a high percentage of VO2max over an endurance race. In athletes with more severe airflow obstruction, the maximum ventilation rate may be reduced and so VO2max may be impaired. The athletes in the present study have adapted to this limitation by being able to sustain a higher %VO2max before the accumulation of blood lactate, which is an advantage during an endurance race. Therefore, with appropriate training and medication, asthmatics can successfully participate in endurance running at a competitive level.  相似文献   

7.
The single-stage treadmill walking test of Ebbeling et al. is commonly used to predict maximal oxygen consumption (.VO(2max)) from a submaximal effort between 50% and 70% of the participant's age-predicted maximum heart rate. The purpose of this study was to determine if this submaximal test correctly predicts .VO(2max) at the low (50% of maximum heart rate) and high (70% of maximum heart rate) ends of the specified heart rate range for males and females aged 18 - 55 years. Each of the 34 participants completed one low-intensity and one high-intensity trial. The two trials resulted in significantly different estimates of .VO(2max) (low-intensity trial: mean 40.5 ml . kg(-1) . min(-1), s = 9.3; high-intensity trial: 47.5 ml . kg(-1) . min(-1), s = 8.8; P < 0.01). A subset of 22 participants concluded their second trial with a .VO(2max) test (mean 47.9 ml . kg(-1) . min(-1), s = 8.9). The low-intensity trial underestimated (mean difference = -3.5 ml . kg(-1) . min(-1); 95% CI = -6.4 to -0.6 ml . kg(-1) . min(-1); P = 0.02) and the high-intensity trial overestimated (mean difference = 3.5 ml . kg(-1) . min(-1); 95% CI = 1.1 to 6.0 ml . kg(-1) . min(-1); P = 0.01) the measured .VO(2max). The predictive validity of Ebbeling and colleagues' single-stage submaximal treadmill walking test is diminished when performed at the extremes of the specified heart rate range.  相似文献   

8.
A loss in total body mass during an ultraendurance performance is usually attributed to dehydration. We identified the changes in total body mass, fat mass, skeletal muscle mass, and selected markers of hydration status in 31 male nonprofessional ultratriathletes participating in a Triple Iron triathlon involving 11.4 km swimming, 540 km cycling and 126.6 km running. Measurements were taken prior to starting the race and after arrival at the finish line. Total body mass decreased by 1.66 kg (SD = 1.92; -5.3 kg to +1.2 kg; p < .001), skeletal muscle mass by 1.00 kg (SD = 0.90; -2.54 kg to +2.07 kg; p < .001), and fat mass by 0.58 kg (SD = 0.78; -1.74 kg to +0.87 kg; p < .001). The decrease in total body mass was associated with the decrease in skeletal muscle mass (r = .44; p < .05) and fat mass (r = .51; p < .05). Total body water and urinary specific gravity did not significantly change. Plasma urea increased significantly (p < .001); the decrease in skeletal muscle mass and the increase in plasma urea were associated (r = .39; p < .05). We conclude that completing a Triple Iron triathlon leads to decreased total body mass due to reduced fat mass and skeletal muscle mass but not to dehydration. The association of decrease in skeletal muscle mass and increased plasma urea suggests a loss in skeletal muscle mass.  相似文献   

9.
The purpose of the present study was to re-examine the relationship between deep body temperature and relative exercise intensity, during running rather than cycling (Saltin and Hermansen, 1966). Twenty male competitive and recreational distance runners, aged 22 + 0.9 years (mean +/- sx), were selected to form two groups, one with high maximal oxygen uptake (VO2max) values (72.8 +/- 0.8 ml x kg(-1) x min(-1)) and the other with moderate values (59.4 +/- 0.7 ml x kg(-1) x min(-1)). The participants completed two 60 min constant-paced treadmill runs at a common speed (absolute intensity) of 10.5 km x h(-1) and at a relative exercise intensity at a speed equivalent to 65% of VO2max. During the relative exercise intensity trial, no differences were found in rectal temperature, skin temperature or heart rate between groups. However, when running at the common speed, differences were identified in rectal temperature. At 60 min, rectal temperature was 37.70 +/- 0.19 degrees C and 38.19 +/- 0.11 degrees C for the high and moderate VO2max groups, respectively (P < 0.05). Sweat lost was significantly higher in the moderate VO2max group (moderate: 1.05 +/- 0.06 kg x h(-1); high: 0.82 +/- 0.08 kg x h(-1); P < 0.05). Heart rates were also different between groups over the first 20 min during the common speed trial (P < 0.05). The results of the present study support the findings of Saltin and Hermansen (1966), in that the set-point at which temperature is maintained is related to the relative exercise intensity.  相似文献   

10.
Previous studies have reported strong correlations between 5-km performance times and maximal oxygen uptake (VO2 max) and also for running speeds equivalent to blood lactate concentrations of 4 mM. However, there is little information on the physiological responses of individuals during races over this distance. Therefore, the aim of the present study was to measure the physiological and metabolic responses of endurance trained male (n = 8) and female (n = 8) runners during a 5-km time trial using an instrumented treadmill. Performance times were 18.77 +/- 1.27 min for the men and 21.80 +/- 1.98 min for the women (P less than 0.01). The corresponding times on the athletics track were 17.68 +/- 0.39 min for the men (P less than 0.05) and 20.70 +/- 2.16 min for the women (N.S.). During the treadmill time trials, both the men and women were able to utilize approximately 90% VO2 max, 82% VE max, 98% HR max and produce similar concentrations of blood lactate. Although the physiological and metabolic responses of these endurance-trained men and women to 5-km treadmill running were similar, the faster running times recorded by the men in this study were the result of their higher VO2 max values.  相似文献   

11.
Thirty-eight female subjects (M +/ SD = 33 +/- 3.0 years) had VO2max measured on the cycle ergometer (M +/- SD = 37.3 +/- 6.4 ml.kg-1.min-1) and on the treadmill (M +/- SD = 41.3 +/- 6.6 ml.kg-1.min-1). VO2max was estimated for each subject from heart rate (HR) at submaximal workloads on the cycle ergometer using the Astrand-Rhyming nomogram (A/R) and the extrapolation method (XTP). VO2max was also estimated from three field tests: 1.5-mile run (RUN) (independent variable [IV] = time), mile walk (WALK) (IV = time, age, HR, gender, body weight), and the Queens College Step Test (ST) (IV = HR during 5-20 s recovery). Repeated measure ANOVA revealed significant mean differences between the criterion cycle ergometer VO2max versus A/R and XTP (20 and 12% overestimation). The WALK, RUN, and ST VO2max values were not significantly different from the criterion treadmill VO2max. The correlation between criterion VO2max estimated from the WALK and RUN were r = .73 (SEE = 4.57 ml,kg-1.min-1) and r = .79 (SEE = 4.13 ml.kg-1.min-1), respectively. The ST, A/R, and XTP had higher SEEs (13-13.5% of the mean) and lower r s (r = .55 to r = .66). These results suggest both the WALK and RUN tests are satisfactory predictors of VO2max in 30 to 39-year-old females.  相似文献   

12.
Abstract

Eight male and eight female runners were matched on performance in a 24.2 km (15 mile) road race (X time ± SD = 115.1 ± 2.2 min for females, 115.8 ± 3.2 min for males). All subjects completed a graded treadmill run during which [Vdot]O 2 and heart rate (HR) were monitored at several submaximal running speeds and at maximal exercise. Blood samples, collected at rest and 3 min after maximal exercise, were analyzed for hematocrit and hemoglobin (Hb), lactic acid (LA) and 2,3-diphosphoglyceric acid (2,3-DPG) concentrations. Body composition was assessed via hydrostatic weighing. Group comparisons revealed that the males were taller, heavier, and higher in Hb than the females (p < .05). The sexes did not differ significantly in percentage of body fat or in [Vdot]O 2 (ml · kg –1 · min –1 ), HR, respiratory exchange ratio, or ventilatory equivalent of oxygen during submaximal running or at maximal exercise (p > .05). 2,3-DPG was higher in the females when expressed relative to Hb (p < .05). These data indicate that female and male distance runners of equal performance levels are very similar in body composition and in metabolic and cardiorespiratory responses to exercise. The higher Hb observed in males may have been offset in part by the females' higher 2,3-DPG/Hb ratio.  相似文献   

13.
The aim of this study was to monitor longitudinal changes in young people's submaximal oxygen uptake (VO 2 ) responses during horizontal treadmill running at 8 km h -1 . The 236 participants (118 boys, 118 girls) were aged 11.2 +/- 0.4 years (mean +/- s) at the onset of the study. Submaximal VO 2 , peak VO 2 and anthropometry were recorded annually for three consecutive years. The data were analysed using multi-level regression modelling within a multiplicative, allometric framework. The initial model examined sex, age and maturity-related changes in submaximal VO 2 relative to body mass as the sole anthropometric covariate. Our results demonstrate that the conventional ratio standard ml kg -1 min -1 does not adequately describe the true relationship between body mass and submaximal VO 2 during this period of growth. The effects of maturity and age were non-significant, but girls consumed significantly less VO 2 than boys running at 8 km h -1 . In subsequent models, stature was shown to be a significant explanatory variable, but this effect became non-significant when the sum of two skinfolds was added. Thus, within this population, submaximal VO 2 responses were explained predominantly by changes in body mass and skinfold thicknesses, with no additional maturity-related increments. When differences in body mass and skinfolds were controlled for, there was still a difference between the sexes in submaximal VO 2 , with girls becoming increasingly more economical with age.  相似文献   

14.
Longitudinal changes in submaximal oxygen uptake in 11- to 13-year-olds   总被引:3,自引:0,他引:3  
The aim of this study was to monitor longitudinal changes in young people's submaximal oxygen uptake (VO2) responses during horizontal treadmill running at 8 km x h(-1). The 236 participants (118 boys, 118 girls) were aged 11.2+/-0.4 years (mean +/- s) at the onset of the study. Submaximal VO2, peak VO2 and anthropometry were recorded annually for three consecutive years. The data were analysed using multi-level regression modelling within a multiplicative, allometric framework. The initial model examined sex, age and maturity-related changes in submaximal VO2 relative to body mass as the sole anthropometric covariate. Our results demonstrate that the conventional ratio standard ml x kg(-1) x min(-1) does not adequately describe the true relationship between body mass and submaximal VO2 during this period of growth. The effects of maturity and age were non-significant, but girls consumed significantly less VO2 than boys running at 8 km x h(-1). In subsequent models, stature was shown to be a significant explanatory variable, but this effect became non-significant when the sum of two skinfolds was added. Thus, within this population, submaximal VO2 responses were explained predominantly by changes in body mass and skinfold thicknesses, with no additional maturity-related increments. When differences in body mass and skinfolds were controlled for, there was still a difference between the sexes in submaximal VO2, with girls becoming increasingly more economical with age.  相似文献   

15.
It is not known whether the seated or standing position favours performance during intensive bouts of uphill cycling. The following hypotheses were therefore tested: (1) the standing position results in better performance at a high power output, while (2) the seated position is best at a moderate power output. We also assessed the seated-standing transition intensity, above which seated cycling should be superseded by standing cycling for maximization of performance. Ten male cyclists (mean age 27 years, s = 3; height 1.82 m, s = 0.07; body mass 75.2 kg, s = 7.0; VO2max 70.0 ml.kg(-1).min(-1), s = 5.2) performed seated and standing treadmill cycling to exhaustion at 10% grade and at four power outputs ranging from 86% to 165% of their power output at maximal oxygen uptake (Wmax). Power output at maximal oxygen uptake was obtained during determination of VO2max. There was no difference in time to exhaustion between the two cycling positions at 86% of Wmax (P = 0.29). All participants performed best at the highest power output (165% of Wmax) when standing (P = 0.002). An overall seated-standing transition intensity of 94% of Wmax was identified. Thus, in general, cyclists may choose either the standing or seated position for maximization of performance at a submaximal intensity of 86% of Wmax, while the standing position should be used at intensities above 94% of Wmax and approaching 165% of Wmax.  相似文献   

16.
铁人三项运动是体育运动耐力性项目之一,由游泳、公路自行车、公路长跑三个项目按顺序组成。近年来,通过对铁人三项运动成绩提高的一些潜在的因素进行相关的研究,较为一致的建议是在游泳或自行车运动时,采用运动追随可获得益处。其他的策略因素包括自行车运动或跑步时选择运动节奏,可能会影响到铁人三项的整体运动成绩。  相似文献   

17.
运动对无氧阈、最大吸氧量的影响与心功能的关系   总被引:3,自引:0,他引:3  
两年游泳系统训练后,男女运动员VO2max绝对值和相对值都无显著性变化,无氧阈明显提高。表明,AT的显著改善并不需要VO2max明显提高。训练后,AT和心泵血功能都有显著性提高,并且CO与AT的相关比CO与VO2max相关更为密切,提示,AT提高与心泵血功能变化有关,心功能可能是影响AT的重要因素。训练使心脏舒张功能得以改善,这是心脏对运动的又一适应。  相似文献   

18.
周志雄  季钢  张凡 《体育科学》2006,26(11):75-79,87
为了分析《学生体质健康标准》中心血管功能评价指标的同质性和有效性,对87名普通大学生进行体质健康测试和最大耗氧量测试。研究结果表明,大学生的台阶测试得分和耐久跑成绩得分无显著差异;台阶测试得分与耐久跑之间无显著线性相关关系(r=-0.086,P〉0.05);台阶测试和耐久跑指标之间无同质性;大学生最大耗氧量与台阶试验测试值和台阶试验得分无显著线性相关(r〈0.15,P〉0.05),大学生最大耗氧量与耐久跑成绩和得分之间也无显著线性相关。  相似文献   

19.
Traditionally, it has been assumed that during middle-distance running oxygen uptake (VO2) reaches its maximal value (VO2max) providing the event is of a sufficient duration; however, this assumption is largely based on observations in individuals with a relatively low VO2max. The aim of this study was to determine whether VO2max is related to the VO2 attained (i.e. VO2peak) during middle-distance running on a treadmill. Fifteen well-trained male runners (age 23.3 +/- 3.8 years, height 1.80 +/- 0.10 m, body mass 76.9 +/- 10.6 kg) volunteered to participate in the study. The participants undertook two 800-m trials to examine the reproducibility of the VO2 response. These two trials, together with a progressive test to determine VO2max, were completed in a randomized order. Oxygen uptake was determined throughout each test using 15-s Douglas bag collections. Following the application of a 30-s rolling average, the highest VO2 during the progressive test (i.e. VO2max) was compared with the highest VO2 during the 800-m trials (i.e. VO2peak) to examine the relationship between VO2max and the VO2 attained in the 800-m trials. For the 15 runners, VO2max was 58.9 +/- 7.1 ml x kg(-1) x min(-1). Two groups were formed using a median split based on VO2max. For the high and low VO2max groups, VO2max was 65.7 +/- 3.0 and 52.4 +/- 1.8 ml x kg(-1) x min(-1) respectively. The limits of agreement (95%) for test-retest reproducibility for the VO2 attained during the 800-m trials were +/- 3.5 ml x kg(-1) x min(-1) for a VO2peak of 50.6 ml x kg(-1) x min(-1) (the mean VO2peak for the low VO2max group) and +/- 2.3 ml x kg(-1) x min(-1) for a VO2peak of 59.0 ml x kg(-1) x min(-1) (the mean VO2peak for the high VO2max group), with a bias in VO2peak between the 800-m runs (i.e. the mean difference) of 1.2 ml x kg(-1) x min(-1). The VO2peak for the 800-m runs was 54.8 +/- 4.9 ml x kg(-1) x min(-1) for all 15 runners. For the high and low VO2max groups, VO2peak was 59.0 +/- 3.3 ml x kg(-1) x min(-1) (i.e. 90% VO2max) and 50.6 +/- 2.0 ml x kg(-1) x min(-1) (i.e. 97% VO2max) respectively. The negative relationship (-0.77) between VO2max and % VO2max attained for all 15 runners was significant (P = 0.001). These results demonstrate that (i) reproducibility is good and (ii) that VO2max is related to the %VO2max achieved, with participants with a higher VO2max achieving a lower %VO2max in an 800-m trial on a treadmill.  相似文献   

20.
Seven elite male cross-country skiers trained for 3 weeks at an altitude of 1900 m. Haemoglobin concentration ([Hb]), haematocrit (Hct) (obtained from venous blood), maximal oxygen uptake (VO2 max) and energy expenditure during a standard submaximal workload were measured before and after training at altitude, and 1 year later while training at sea level (control). Both [Hb] and Hct increased significantly, and the skiers with the lowest initial [Hb] and Hct experienced the largest increases during training at altitude. The increase in blood lactate (BLa) concentration (using haemolysed capillary blood) during a standard submaximal exercise test was significantly lower after training at altitude than before it or 1 year later (control). A significant correlation was found between the magnitude of increase in [Hb] and Hct and the difference in the lactate response to the standard submaximal workload pre- and post-altitude training. Although VO2 max remained unchanged, lower BLa concentration during the submaximal test probably reflects an improved ability to exercise at higher submaximal workloads shortly after training at altitude compared with pre-altitude training. It is suggested that subjects with low initial [Hb] and Hct improve their aerobic performance capacity most during altitude training.  相似文献   

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