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1.
Ten basketball players and two coaches ([Vdot]O2 max = 51.08 ml/kg · min) were studied at their place of residence in Chadron, Nebraska (1,000 m, PB = 661 mm Hg), and 6 days later in Laramie, Wyoming (2,200 m, PB = 584 mm Hg). Subjects rode the bicycle ergometer through several submaximal workloads until voluntary exhaustion. Laramie tests took place within 8 hours after arrival and at the same time of day as the Chadron tests. Submaximal heart rate, oxygen consumption, pulmonary ventilation, carbon dioxide production, respiratory quotient, and perceived exertion were not significantly altered by the altitude change; however, ventilatory equivalent was significantly higher in Laramie (p < .05). The hypoxia-induced decrease in the anaerobic threshold ( workload = 906 kpm/min at both sites) which was hypothesized was not observed. Likewise, resting hematocrit and hemoglobin were not affected by the 1,200 m altitude increment (44.88 vs. 44.53% and 15.39 vs. 15.01 gm%, respectively). Maximum aerobic power, heart rate, and ventilation were not statistically significant. Maximum ventilatory equivalent increased and vital capacity decreased significantly in Laramie. In general, basketball players with moderately high aerobic power who reside at an altitude of 1,000 m do not display the hypoxic response to an altitude of 2,200 m expected of sea level residents and aerobically trained athletes.  相似文献   

2.
The literature related to Borg's ratings of perceived exertion (RPE) scale has revealed inconsistencies about the strength of the relationship between ratings of perceived exertion and various physiological criterion measures, such as heart rate, blood lactate concentration, percent maximal oxygen uptake (%VO2max), oxygen uptake (VO2), ventilation and respiration rate. Using sex of participants, fitness, type of RPE scale used, type of exercise, exercise protocol, RPE mode and study quality, we undertook a meta-analysis to determine the strength of the relationship between RPE scores and the six aforementioned physiological measures. The weighted mean validity coefficients were 0.62 for heart rate, 0.57 for blood lactate, 0.64 for %VO2max 0.63 for VO2, 0.61 for ventilation and 0.72 for respiration rate. Analysis of moderator variables revealed that the following study features could account for the variation of results across studies: heart rate--fitness, type of exercise, protocol and RPE mode; blood lactate concentration--sex, RPE scale; VO2--sex, exercise type, RPE mode; ventilation--sex, RPE mode; respiration rate--exercise protocol, RPE mode. The highest correlations between ratings of perceived exertion and the various physiological criterion measures were found in the following conditions: when male participants (whose VO2 or ventilation was measured) were required to maximally exert themselves (measuring %VO2max or ventilation); when the exercise task was unusual [e.g. when participants were swimming, which is less common than walking or running (when heart rate, %VO2max and VO2 are measured)]; or when the 15-point RPE scale (measuring blood lactate concentration) was used. These findings suggest that although Borg's RPE scale has been shown to be a valid measure of exercise intensity, its validity may not be as high as previously thought (r = 0.80-0.90), except under certain conditions.  相似文献   

3.
The aim of this study was to objectively quantify ratings of perceived enjoyment using the Physical Activity Enjoyment Scale following high-intensity interval running versus moderate-intensity continuous running. Eight recreationally active men performed two running protocols consisting of high-intensity interval running (6 × 3 min at 90% VO(2max) interspersed with 6 × 3 min active recovery at 50% VO(2max) with a 7-min warm-up and cool down at 70% VO(2max)) or 50 min moderate-intensity continuous running at 70% VO(2max). Ratings of perceived enjoyment after exercise were higher (P < 0.05) following interval running compared with continuous running (88 ± 6 vs. 61 ± 12) despite higher (P < 0.05) ratings of perceived exertion (14 ± 1 vs. 13 ± 1). There was no difference (P < 0.05) in average heart rate (88 ± 3 vs. 87 ± 3% maximum heart rate), average VO(2) (71 ± 6 vs. 73 ± 4%VO(2max)), total VO(2) (162 ± 16 vs. 166 ± 27 L) or energy expenditure (811 ± 83 vs. 832 ± 136 kcal) between protocols. The greater enjoyment associated with high-intensity interval running may be relevant for improving exercise adherence, since running is a low-cost exercise intervention requiring no exercise equipment and similar relative exercise intensities have previously induced health benefits in patient populations.  相似文献   

4.
对不同运动负荷方案下的心率及RPE效度研究   总被引：1，自引：0，他引：1  
目的:分析男子在不同运动负荷方案下,Borg的公式HR=RPEx10(心率=主观感觉运动负荷等级×10)估算出的心率是否可靠,验证RPE值是否与心率表现出高度相关,为提高RPE(主观感觉运动负荷评估表)评价的有效性与客观性提供一定依据。方法:测定7名在校体育学院男生的最大耗氧量,自行车递增负荷运动以及恒定负荷运动中各等级负荷末1 min心率、耗氧量、呼吸频率和RPE值等指标。结果:在递增负荷运动中,受试对象评定RPE等级的估算心率其特点呈现低负荷及中、高负荷时偏低,最大负荷时偏高的特点,并且,中、高负荷及最大负荷运动时RPE估算心率值与实测心率值有显著差异(P>0.05)。在恒定负荷运动中,受试对象的RPE估算心率值呈现整体偏低的特点。RPE与心率、呼吸频率,呼吸商、摄氧量等几项指标相关系数远远低于文献记录的相关系数0.80～0.90,且呼吸频率与RPE值的相关性高于心率。结论:公式HR=RPEx10得出的估算心率值,在男子进行递增负荷运动时可能不够准确,而在恒定负荷运动中估算效果更佳。在采用不同评价方式评价RPE时,估算心率与实际心率之差值幅度随评价时间延长而递增。呼吸频率与心率相比,在反映RPE指标时可能...  相似文献   

5.
Abstract

The aim was to evaluate the effects of judo combat on the athletes’ postural control (PC) and physiological loading before, during and after a simulated match. Seventeen under-20 regional and national level athletes completed one modified 7-min match. At baseline, during the combat (3rd and 7th minutes) and 2-min post-match centre of pressure (CoP) parameters were assessed. Heart rate (HR), blood lactate (BLa) and rating of perceived exertion (RPE) and local RPE (LRPE) were collected. Significant increments were observed in CoP mean positioning and velocity at 3rd and 7th minutes, but the CoP deviation in both axes was unaffected. HR and BLa were elevated at 3rd and 7th minutes, and they remained elevated 2-min post-match. However, CoP returned to baseline 2-min post-match. RPE was elevated at 3rd and 7th minutes and the greatest effort was displayed in the Deltoid and Quadriceps. Thus, one simulated judo match stimulates a significant metabolic response and balance is degraded, with the greatest effects on the anterior–posterior axis and it recovers to baseline level after 2 min of passive rest. The physiological load cannot be regarded as a potential predictor variable of CoP. Overall, a judo match predominantly affects the upper body than the other body parts.  相似文献   

6.
Purpose: The purpose of this investigation was to examine the effects of a submaximal running warm-up on running performance in male endurance athletes (n = 16, Mage = 21 ± 2 years, MVO2max = 69.3 ± 5.1 mL/kg/min). Method: Endurance performance was determined by a 30-min distance trial after control and submaximal running warm-up conditions in a randomized crossover fashion. The warm-up began with 5 min of quiet sitting, followed by 6 min of submaximal running split into 2-min intervals at speeds corresponding to 45%, 55%, and 65% maximal oxygen consumption (VO2max). A 2-min walk at 3.2 km/hr concluded the 13-min warm-up protocol. For the control condition, participants sat quietly for 13 min. VO2 and heart rate (HR) were determined at Minutes 0, 5, and 13 of the pre-exercise protocol in each condition. Results: At the end of 13 min prior to the distance trial, mean VO2 (warm-up = 14.1 ± 2.2 mL/kg/min vs. control = 5.5 ± 1.7 mL/kg/min) and mean HR (warm-up = 105 ± 11 bpm vs. control = 67 ± 11 bpm) were statistically greater (p < .001) in the warm-up condition compared with the control condition. The distance run did not statistically differ (p = .37) between the warm-up (7.8 ± 0.5 km) and control (7.7 ± 0.6 km) conditions; however, effect size calculation revealed a small effect (d = 0.2) in favor of the warm-up condition. Thus, the warm-up employed may have important and practical implications to determine placing among high-level athletes in close races. Conclusions: These findings suggest a submaximal running warm-up may have a small but critical effect on a 30-min distance trial in competitive endurance athletes. Further, the warm-up elicited increases in physiological variables VO2 and HR prior to performance; thus, a submaximal specific warm-up should warrant consideration.  相似文献   

7.
Abstract

This study was designed to examine the magnitude and duration of excess postexercise oxygen consumption (EPOC) following upper body exercise, using lower body exercise for comparison. On separate days and in a counterbalanced order, eight subjects (four male and four female) performed a 20-min exercise at 60% of mode-specific peak oxygen uptake (VO2) using an arm crank and cycle ergometer. Prior to each exercise, baseline VO2 and heart rate (HR) were measured during the final 15 min of a 45-min seated rest. VO2 and HR were measured continuously during the postexercise period until baseline VO2 was reestablished. No significant difference between the two experimental conditions was found for magnitude of EPOC (t [7] = 0.69, p > .05). Mean (± SD) values were 9.2 ± 3.3 and 10.4 ± 5.8 kcal for the arm crank and cycle ergometer exercises, respectively. Duration of EPOC was relatively short and not significantly different (t [7] = 0.24, p > .05) between the upper body (22.9 ± 13.7 min) and lower body (24.2 ± 19.4 min) exercises. Within the framework of the chosen exercise conditions, these results suggest EPOC may be related primarily to the relative metabolic rate of the active musculature, as opposed to the absolute exercise VO2 or quantity of active muscle mass associated with these two types of exercise.  相似文献   

8.
This study aimed to investigate whether treadmill versus overground soccer match simulations have similar effects on knee joint mechanics during side cutting. Nineteen male recreational soccer players completed a 45-min treadmill and overground match simulation. Heart rate (HR) and rating of perceived exertion (RPE) were recorded every 5 min. Prior to exercise (time 0 min), at “half-time” (time 45 min) and 15 min post-exercise (time 60 min), participants performed five trials of 45° side-cutting manoeuvres. Knee abduction moments and knee extension angles were analysed using two-way repeated measures analysis of variance (α = 0.05). Physiological responses were significantly greater during the overground (HR 160 ± 7 beats ? min?1; RPE 15 ± 2) than the treadmill simulation (HR 142 ± 5 beats ? min?1; RPE 12 ± 2). Knee extension angles significantly increased over time and were more extended at time 60 min compared with time 0 min and time 45 min. No significant differences in knee abduction moments were observed. Although knee abduction moments were not altered over time during both simulations, passive rest during half-time induced changes in knee angles that may have implications for anterior cruciate ligament injury risk.  相似文献   

9.
It has previously been shown that the metabolic acidaemia induced by a continuous warm-up at the 'lactate threshold' is associated with a reduced accumulated oxygen deficit and decreased supramaximal performance. The aim of this study was to determine if an intermittent, high-intensity warm-up could increase oxygen uptake (VO2) without reducing the accumulated oxygen deficit, and thus improve supramaximal performance. Seven male 500 m kayak paddlers, who had represented their state, volunteered for this study. Each performed a graded exercise test to determine VO2max and threshold parameters. On subsequent days and in a random, counterbalanced order, the participants then performed a continuous or intermittent, high-intensity warm-up followed by a 2 min, all-out kayak ergometer test. The continuous warm-up consisted of 15 min of exercise at approximately 65% VO2max. The intermittent, high-intensity warm-up was similar, except that the last 5 min was replaced with five 10 s sprints at 200% VO2max, separated by 50 s of recovery at approximately 55% VO2max. Significantly greater (P < 0.05) peak power (intermittent vs continuous: 629 +/- 199 vs 601 +/- 204 W) and average power (intermittent vs continuous: 328 +/- 39.0 vs 321 +/- 42.4 W) were recorded after the intermittent warm-up. There was no significant difference between conditions for peak VO2, total VO2 or the accumulated oxygen deficit. The results of this study indicate that 2 min all-out kayak ergometer performance is significantly better after an intermittent rather than a continuous warm-up.  相似文献   

10.
It has previously been shown that the metabolic acidaemia induced by a continuous warm-up at the 'lactate threshold' is associated with a reduced accumulated oxygen deficit and decreased supramaximal performance. The aim of this study was to determine if an intermittent, high-intensity warm-up could increase oxygen uptake (V02) without reducing the accumulated oxygen deficit, and thus improve supramaximal performance. Seven male 500 m kayak paddlers, who had represented their state, volunteered for this study. Each performed a graded exercise test to determine V02max and threshold parameters. On subsequent days and in a random, counterbalanced order, the participants then performed a continuous or intermittent, high-intensity warm-up followed by a 2 min, all-out kayak ergometer test. The continuous warm-up consisted of 15 min of exercise at approximately 65% V02max. The intermittent, high-intensity warm-up was similar, except that the last 5 min was replaced with five 10 s sprints at 200% V02max, separated by 50 s of recovery at ~55% V02max. Significantly greater (P<0.05) peak power (intermittent vs continuous: 629 ± 199 vs 601 ± 204W) and average power (intermittent vs continuous: 328±39.0 vs 321 ±42.4 W) were recorded after the intermittent warm-up. There was no significant difference between conditions for peak V02, total V02 or the accumulated oxygen deficit. The results of this study indicate that 2 min all-out kayak ergometer performance is significantly better after an intermittent rather than a continuous warm-up.  相似文献   

11.
The purpose of this study was to assess the validity of predicting the maximal oxygen uptake (VO2(max)) of sedentary men from sub-maximal VO2 values obtained during a perceptually regulated exercise test. Thirteen healthy, sedentary males aged 29-52 years completed five graded exercise tests on a cycle ergometer. The first and fifth test involved a graded exercise test to determine VO2(max). The two maximal graded exercise tests were separated by three sub-maximal graded exercise tests, perceptually regulated at 3-min RPE intensities of 9, 11, 13, 15, and 17 on the Borg ratings of perceived exertion (RPE) scale, in that order. After confirmation that individual linear regression models provided the most appropriate fit to the data, the regression lines for the perceptual ranges 9-17, 9-15, and 11-17 were extrapolated to RPE 20 to predict VO2(max). There were no significant differences between VO2(max) values from the graded exercise tests (mean 43.9 ml x kg(-1) x min(-1), s = 6.3) and predicted VO2(max) values for the perceptual ranges 9-17 (40.7 ml x kg(-1) x min(-1), s = 2.2) and RPE 11-17 (42.5 ml x kg(-1) x min(-1), s = 2.3) across the three trials. The predicted VO2(max) from the perceptual range 9-15 was significantly lower (P < 0.05) (37.7 ml x kg(-1) x min(-1), s = 2.3). The intra-class correlation coefficients between actual and predicted VO2(max) for RPE 9-17 and RPE 11-17 across trials ranged from 0.80 to 0.87. Limits of agreement analysis on actual and predicted VO2 values (bias +/- 1.96 x S(diff)) were 3.4 ml x kg(-1) x min(-1) (+/- 10.7), 2.4 ml x kg(-1) x min(-1) (+/- 9.9), and 3.7 ml x kg(-1) x min(-1) (+/- 12.8) (trials 1, 2, and 3, respectively) of RPE range 9-17. Results suggest that a sub-maximal, perceptually guided graded exercise test provides acceptable estimates of VO2(max) in young to middle-aged sedentary males.  相似文献   

12.
This study was designed to examine the magnitude and duration of excess postexercise oxygen consumption (EPOC) following upper body exercise, using lower body exercise for comparison. On separate days and in a counterbalanced order, eight subjects (four male and four female) performed a 20-min exercise at 60% of mode-specific peak oxygen uptake (VO2) using an arm crank and cycle ergometer. Prior to each exercise, baseline VO2 and heart rate (HR) were measured during the final 15 min of a 45-min seated rest. VO2 and HR were measured continuously during the postexercise period until baseline VO2 was reestablished. No significant difference between the two experimental conditions was found for magnitude of EPOC (t [7] = 0.69, p greater than .05). Mean (+/- SD) values were 9.2 +/- 3.3 and 10.4 +/- 5.8 kcal for the arm crank and cycle ergometer exercises, respectively. Duration of EPOC was relatively short and not significantly different (t [7] = 0.24, p greater than .05) between the upper body (22.9 +/- 13.7 min) and lower body (24.2 +/- 19.4 min) exercises. Within the framework of the chosen exercise conditions, these results suggest EPOC may be related primarily to the relative metabolic rate of the active musculature, as opposed to the absolute exercise VO2 or quantity of active muscle mass associated with these two types of exercise.  相似文献   

13.
  相似文献   

14.
The aim of this study was to assess the effect of time of day on physiological responses to running at the speed at the lactate threshold. After determination of the lactate threshold, using a standard incremental protocol, nine male runners (age 26.3 +/- 5.7 years, height 1.77 +/- 0.07 m, mass 73.1 +/- 6.5 kg, lactate threshold speed 13.6 +/- 1.6 km x h(-1); mean +/- s) completed a standardized 30 min run at lactate threshold speed, twice within 24 h (07:00-09:00 h and 18:00-21:00 h). Core body temperature, heart rate, minute ventilation, oxygen uptake, carbon dioxide expired, respiratory exchange ratio and capillary blood lactate were measured at rest, after a warm-up and at 10, 20 and 30 min during the run. In addition, the rating of perceived exertion was reported every 10 min during the run. Significant diurnal variation was observed only for body temperature (36.9 +/- 0.9 degrees C vs 37.3 +/- 0.3 degrees C) and respiratory exchange ratio at rest (0.86 +/- 0.01 vs 0.89 +/- 0.07) (P < 0.05). Diurnal variation persisted for body temperature throughout the warm-up (37.1 +/- 0.2 degrees C vs 37.5 +/- 0.3 degrees C) and during exercise (36.2 +/- 0.6 degrees C vs 38.6 +/- 0.4 degrees C), but only during the warm-up for the respiratory exchange ratio (0.85 +/- 0.05 vs 0.87 +/- 0.02) (P < 0.05). The rating of perceived exertion was significantly elevated during the morning trial (12.7 +/- 0.9 vs 11.9 +/- 1.2) (P < 0.05). These findings suggest that, despite the diurnal variation in body temperature, other physiological responses to running at lactate threshold speed are largely unaffected. However, a longer warm-up may be required in morning trials because of a slower increase in body temperature, which could have an impact on ventilation responses and ratings of perceived exertion.  相似文献   

15.
Purpose: To compare the physiological and perceptual responses of the upper and lower body to all-out cyclical sprints with short or long rest periods between sprints.

Methods: Ten recreationally trained males completed four 10?×?10?s sprint protocols in a randomized order: upper body with 30?s and 180?s of rest between sprints, and lower body with 30?s and 180?s of rest between sprints. Additionally, maximum voluntary contractions (MVC) were measured at pre-sprint and post-sprints 5 and 10. Normalized (% of first sprint) peak power, MVC, heart rate (HR) and rating of perceived exertion (RPE) were compared between upper and lower body within the same recovery period, and absolute values (Watts, bpm, RPE scores) were compared within the same body part and between recovery periods.

Results: Trivial differences were identified in normalized peak power, HR and RPE values between the upper and lower body in both recovery conditions (<2%, d?≤?0.1), but MVC forces were better maintained with the upper body (～9.5%, d?=?1.0) in both recovery conditions. Absolute peak power was lower (～147?Watts, d?=?1.3), and HR was higher (～10?bpm, d?=?0.73) in the 30?s compared to 180?s condition in both the upper and lower body whereas RPE scores were similar (<0.6?RPE units, d?≤?0.1). Despite the reductions in peak power, MVC forces were better maintained in the 30?s condition in both upper (2.5?kg, d?=?0.4) and lower (7.5?kg, d?=?0.7) body.

Conclusions: Completing a commonly used repeated sprint protocol with the upper and lower body results in comparable normalized physiological and perceptual responses.  相似文献   

16.
Cui Y  Liu X  Liu X  Wu J  Zhao M  Ren J  Yang J  Gu F  Wang C 《Journal of sports sciences》2011,29(4):363-371
The aim of this study was to examine the exercise workload of the 3rd Series of National Broadcast Calisthenics for Elementary and Middle School Students. Altogether, 120 students aged 11-17 years were randomly selected from elementary and middle schools to participate in the study. Each participant performed a cycle ergometer test to obtain maximum oxygen uptake ([Vdot]O(2max)) and maximum heart rate values. In the laboratory, oxygen uptake ([Vdot]O(2)), metabolic equivalents (METs), and heart rate were recorded continuously throughout a calisthenics session performed by the participants. Ratings of perceived exertion (RPE) were also recorded. Throughout the calisthenics session, mean percentage of [Vdot]O(2) reserve varied from 30.7% to 41.2%, mean percentage of heart rate reserve from 39.0% to 56.9%, and mean RPE from 9.0 to 10.4. The mean energy cost during most of the segments across the four routines of calisthenics was significantly higher (P?相似文献   

17.
The aim of this study was to compare the physiological and psychological responses of cyclists riding on a hard tail bicycle and on a full suspension bicycle. Twenty males participated in two series of tests. A test rig held the front axle of the bicycle steady while the rear wheel rotated against a heavy roller with bumps (or no bumps) on its surface. In the first series of tests, eight participants (age 19-27 years, body mass 65-82 kg) were tested on both the full suspension and hard tail bicycles with and without bumps fitted to the roller. The second series of test repeated the bump tests with a further six participants (age 22-31 years, body mass 74-94 kg) and also involved an investigation of familiarization effects with the final six participants (age 21-30 years, body mass 64-80 kg). Heart rate, oxygen consumption (VO(2)), rating of perceived exertion (RPE) and comfort were recorded during 10 min sub-maximal tests. Combined data for the bumps tests show that the full suspension bicycle was significantly different (P < 0.001) from the hard tail bicycle on all four measures. Oxygen consumption, heart rate and RPE were lower on average by 8.7 (s = 3.6) ml . kg(-1) . min(-1), 32.1 (s = 12.1) beats . min(-1) and 2.6 (s = 2.0) units, respectively. Comfort scores were higher (better) on average by 1.9 (s = 0.8) units. For the no bumps tests, the only statistically significant difference (P = 0.008) was in VO(2), which was lower for the hard tail bicycle by 2.2 (s = 1.7) ml . kg(-1) . min(-1). The results indicate that the full suspension bicycle provides a physiological and psychological advantage over the hard tail bicycle during simulated sub-maximal exercise on bumps.  相似文献   

18.
The aim of this study was to assess the effect of time of day on physiological responses to running at the speed at the lactate threshold. After determination of the lactate threshold, using a standard incremental protocol, nine male runners (age 26.3 - 5.7 years, height 1.77 - 0.07 m, mass 73.1 - 6.5 kg, lactate threshold speed 13.6 - 1.6 km· h -1 ; mean - s ) completed a standardized 30 min run at lactate threshold speed, twice within 24 h (07:00- 09:00 h and 18:00-21:00 h). Core body temperature, heart rate, minute ventilation, oxygen uptake, carbon dioxide expired, respiratory exchange ratio and capillary blood lactate were measured at rest, after a warm-up and at 10, 20 and 30 min during the run. In addition, the rating of perceived exertion was reported every 10 min during the run. Significant diurnal variation was observed only for body temperature (36.9 - 0.9°C vs 37.3 - 0.3°C) and respiratory exchange ratio at rest (0.86 - 0.01 vs 0.89 - 0.07) ( P ? 0.05). Diurnal variation persisted for body temperature throughout the warm-up (37.1 - 0.2°C vs 37.5 - 0.3°C) and during exercise (36.2 - 0.6°C vs 38.6 - 0.4°C), but only during the warm-up for the respiratory exchange ratio (0.85 - 0.05 vs 0.87 - 0.02) ( P ? 0.05). The rating of perceived exertion was significantly elevated during the morning trial (12.7 - 0.9 vs 11.9 - 1.2) ( P ? 0.05). These findings suggest that, despite the diurnal variation in body temperature, other physiological responses to running at lactate threshold speed are largely unaffected. However, a longer warm-up may be required in morning trials because of a slower increase in body temperature, which could have an impact on ventilation responses and ratings of perceived exertion.  相似文献   

19.
Abstract

The purpose of this study was to examine the effect of bicycle ergometer exercise at varying metabolic intensities upon the heart rate, electromyographic (EMG), and mood state responses to a timed mental arithmetic stressor. Twelve males participated in four experimental conditions: three exercise trials consisting of workloads of 40%, 55%, and 70% of physical work capacity, and an attentional control condition. Daily test protocol involved the following time sequence: habituation, baseline, exercise or control condition (presented in a counterbalanced order), recovery, mental arithmetic, and completion of mood state questionnaire. Results indicated no differential response to the mental arithmetic stressor across the four conditions for the 12 subjects for heart rate, EMG activity, or mood state. Thus, 15 min of exercise at 40%, 55%, and 70% of physical work capacity proved to be no different from an attentional control condition in influencing the physiological and psychological responses to the mental arithmetic stressor.  相似文献   

20.
The purpose of this study was to investigate the effect of skate blade hollow on oxygen consumption during forward skating on a treadmill. Varsity level female hockey players (n = 10, age = 21.7 years) performed skating tests at three blade hollows [0.25 in (6.35 mm), 0.50 in (12.7 mm), and 0.75 in (19.05 mm)]. The subjects skated for four minutes at three submaximal velocities (12, 14 and 16 km h−1), separated by five minutes of passive recovery. In addition, a VO2max test was performed on the day that the subjects skated at the 0.50 in hollow. The VO2max test commenced at 14 km h−1 and increased by 1 km h−1 each minute until volitional exhaustion was achieved. Four variables were measured for each skating bout, volume of gas expired (V E), volume of oxygen consumed (VO 2), heart rate (HR) and rating of perceived exertion (RPE). No significant differences (p < 0.05) were found in any of the four test variables (V E, VO2, HR, RPE) across the three skate hollows. These results show that when skating on a treadmill at submaximal velocities, skate blade hollow has no significant effect onV E, VO2, HR or RPE.  相似文献   

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