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1.
Abstract

We followed up on recent findings demonstrating that enhancing performers' expectancies can improve their performance. Specifically, we examined whether providing experienced runners with positive feedback regarding their movement efficiency would increase running efficiency. Two groups of experienced runners ran on a treadmill at 75% of their maximum oxygen consumption ([Vdot]O2max) for 10 min. One group (enhanced expectancy) was provided with (fabricated) feedback about the efficiency of their running style every 2 min. A control group was not given feedback. Oxygen consumption decreased in the enhanced expectancy group across measurement times (every 2 min for 10 min), but remained the same in the control group. In addition, performance perceptions changed only in the enhanced expectancy group, indicating a perception of greater ease of running and reduced fatigue when assessed after compared with before running. Finally, positive affect increased from a pre- to a post-test in the enhanced expectancy group, in contrast to the control group. Our findings show that enhanced expectancies can have a positive effect on movement efficiency and running experience. They add to the accumulating evidence for the social-cognitive-affective-motor nature of motor performance.  相似文献   

2.
The authors examined the individual and combined influences of 2 factors that have been shown to benefit motor learning: an external focus of attention and enhanced performance expectancies. Another purpose of this study was to gain further insight into the mechanisms underlying these variables. In a factorial design, participants learning a novel motor skill (i.e., throwing with the non-dominant arm) were or were not given external focus instructions, and were or were not provided bogus positive social-comparative feedback to enhance their expectancies. This resulted in 4 groups: external focus, enhanced expectancy, external focus/enhanced expectancy and control. External focus instructions and enhanced expectancies had additive benefits for learning: the external focus/enhanced expectancy group demonstrated the greatest throwing accuracy on both retention and transfer tests, while the accuracy scores of the external focus and enhanced expectancy groups were lower, but higher than those of the control group. Furthermore, self-efficacy was increased by both external focus and enhanced expectancy, and predicted retention and transfer performance. Positive affect was heightened in the enhanced expectancy and external focus/enhanced expectancy groups after practice and predicted transfer performance. The findings suggest that the learning benefits of an external focus and enhanced expectancies mediate learning through partially different mechanisms.  相似文献   

3.
The purpose of this study was to determine the effects of a verbal and visual feedback system on running technique, ratings of perceived exertion (RPE), and running economy. Twenty‐two female novice runners were randomly assigned to experimental (n = 11) and control (n = 11) groups. The experimental subjects received verbal and visual feedback concerning their running technique prior to and during each training run. Training involved 15 20‐min treadmill running sessions over a 5‐week period. The control group adhered to the same training routine but did not receive feedback concerning their running technique. High‐speed (100 Hz) photography was used to collect biomechanical data. A submaximal oxygen consumption test and Borg's RPE scale were used to collect data concerning running economy and perceived exertion, respectively. Statistical analysis using ANCOVA revealed that the proposed feedback system had a significant (P < 0.01) effect on the experimental group's running technique by affecting the following desired changes relative to the control group: greater relative stride lengths, shorter support time, greater ankle dorsiflexion during support and greater knee flexion during support and non‐support. There were no significant differences between the groups in submaximal VO2 or RPE. The results of this study suggest that verbal and visual feedback are effective means of eliciting modifications in running style in female novice runners. The link between modifications in running style and improvements in running economy and perceived exertion remains unclear.  相似文献   

4.
Abstract

In research on motor control, the detrimental effect of an internal focus of attention on movement execution of well-learned motor skills is a frequently replicated finding. This experimental study was designed to determine whether this effect is observed with physiological variables during endurance exercise. We examined whether the focus of attention can influence running economy (oxygen consumption at a set running speed). Trained runners had to focus their attention on three different aspects while running on a treadmill. For three consecutive 10-min periods, runners concentrated on the running movement, on their breathing, and on their surroundings. Results showed an increased running economy in the external focus condition. In line with research on motor control, endurance sport also shows that an external focus of attention is better than an internal focus in terms of the physiological performance measure of oxygen consumption.  相似文献   

5.
The purpose of this study was to determine the effects of a verbal and visual feedback system on running technique, ratings of perceived exertion (RPE), and running economy. Twenty-two female novice runners were randomly assigned to experimental (n = 11) and control (n = 11) groups. The experimental subjects received verbal and visual feedback concerning their running technique prior to and during each training run. Training involved 15 20-min treadmill running sessions over a 5-week period. The control group adhered to the same training routine but did not receive feedback concerning their running technique. High-speed (100 Hz) photography was used to collect biomechanical data. A submaximal oxygen consumption test and Borg's RPE scale were used to collect data concerning running economy and perceived exertion, respectively. Statistical analysis using ANCOVA revealed that the proposed feedback system had a significant (P less than 0.01) effect on the experimental group's running technique by affecting the following desired changes relative to the control group: greater relative stride lengths, shorter support time, greater ankle dorsiflexion during support and greater knee flexion during support and non-support. There were no significant differences between the groups in submaximal VO2 or RPE. The results of this study suggest that verbal and visual feedback are effective means of eliciting modifications in running style in female novice runners. The link between modifications in running style and improvements in running economy and perceived exertion remains unclear.  相似文献   

6.
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   

7.
BackgroundRunning is becoming an increasingly popular activity among Americans with over 50 million participants. Running shoe research and technology has continued to advance with no decrease in overall running injury rates. A growing group of runners are making the choice to try the minimal or barefoot running styles of the pre-modern running shoe era. There is some evidence of decreased forces and torques on the lower extremities with barefoot running, but no clear data regarding how this corresponds with injuries. The purpose of this survey study was to examine factors related to performance and injury in runners who have tried barefoot running.MethodsThe University of Virginia Center for Endurance Sport created a 10-question survey regarding barefoot running that was posted on a variety of running blogs and Facebook pages. Percentages were calculated for each question across all surveys. Five hundred and nine participants responded with over 93% of them incorporating some type of barefoot running into their weekly mileage.ResultsA majority of the participants (53%) viewed barefoot running as a training tool to improve specific aspects of their running. However, close to half (46%) viewed barefoot training as a viable alternative to shoes for logging their miles. A large portion of runners initially tried barefoot running due to the promise of improved efficiency (60%), an attempt to get past injury (53%) and/or the recent media hype around the practice (52%). A large majority (68%) of runners participating in the study experienced no new injuries after starting barefoot running. In fact, most respondents (69%) actually had their previous injuries go away after starting barefoot running. Runners responded that their previous knee (46%), foot (19%), ankle (17%), hip (14%), and low back (14%) injuries all proceeded to improve after starting barefoot running.ConclusionPrior studies have found that barefoot running often changes biomechanics compared to shod running with a hypothesized relationship of decreased injuries. This paper reports the result of a survey of 509 runners. The results suggest that a large percentage of this sample of runners experienced benefits or no serious harm from transitioning to barefoot or minimal shoe running.  相似文献   

8.
A number of studies have shown that attentional focus instructions can effect running economy. This study assessed spiroergometry, as well as running kinematics as a possible mechanism to explain these effects. Twelve runners had to focus their attention on either their running movement, their breathing or on a video while running on a treadmill at a set, submaximum speed. Spiroergometry and running kinematics were measured. Results revealed worse running economy in both internal focus conditions (breathing and movement) compared to the external focus condition (video), replicating previous findings. In addition, vertical oscillation during the running movement was elevated in the movement compared to the video condition, indicating a less efficient running style. No changes in kinematics were found for the breathing compared to the video condition. Therefore, consciously focusing on the running movement moves runners away from their optimised running pattern and leads to detriments in economy. The decreases in running economy in the breathing condition can be better explained by changes in breathing patterns.  相似文献   

9.
The aim of the present study was to determine the repeatability of a running endurance test using an automated treadmill system that requires no manual input to control running speed. On three separate occasions, 7 days apart, 10 experienced male endurance-trained runners (mean age 32 years, s = 10; VO2peak 61 ml x kg(-1) x min(-1), s = 7) completed a treadmill time trial, in which they were instructed to run as far as possible in 60 min. The treadmill was instrumented with an ultrasonic feedback-controlled radar modulator that spontaneously regulated treadmill belt speed corresponding to the changing running speed of each runner. Estimated running intensity was 70% VO2peak (s = 11) and the distance covered 13.5 km (s = 2), with no difference in mean performances between trials. The coefficient of variation, estimated using analysis of variance, with participant and trial as main effects, was 1.4%. In summary, the use of an automated treadmill system improved the repeatability of a 60-min treadmill time trial compared with time trials in which speed is controlled manually. The present protocol is a reliable method of assessing endurance performance in endurance-trained runners.  相似文献   

10.
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 1‐1’ (V‐2 mM) or 4 mmol 1‐1 (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 <0.05). Therefore the results 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   

11.
Performer autonomy has been shown to contribute to effective motor performance and learning. Autonomy support is therefore a key factor in the OPTIMAL theory of motor learning (Wulf, G., & Lewthwaite, 2016). The purpose of the present study was to examine whether supporting individuals’ need for autonomy by giving them choices would increase movement efficiency. Such a finding would be consistent with the OPTIMAL theory prediction that autonomy facilitates the coupling of goals and actions. Participants (N = 32) were asked to run at a submaximal intensity (65% of VO2 max) for 20 minutes. Before the run, participants in a choice group were able to choose 5 of 10 photos as well as the order in which they would be shown to them on a computer screen during the run. Control group participants were shown the same photos, in the same order, chosen by their counterparts in the choice group. Throughout the run, oxygen consumption and heart rate were significantly lower in the choice group than the control group. Thus, providing autonomy support resulted in enhanced running efficiency. The present findings are in line with the notion that autonomy facilitates goal-action coupling.  相似文献   

12.
Running economy is a reflection of the amount of inspired oxygen required to maintain a given velocity and is considered a determining factor for running performance. Athletic footwear has been advocated as a mechanism by which running economy can be enhanced. New commercially available footwear has been developed in order to increase energy return, although their efficacy has not been investigated. This study aimed to examine the effects of energy return footwear on running economy in relation to conventional running shoes. Twelve male runners completed 6-min steady-state runs in conventional and energy return footwear. Overall, oxygen consumption (VO2), heart rate, respiratory exchange ratio, shoe comfort and rating of perceived exertion were assessed. Moreover, participants subjectively indicated which shoe condition they preferred for running. Differences in shoe comfort and physiological parameters were examined using Wilcoxon signed-rank tests, whilst shoe preferences were tested using a chi-square analysis. The results showed that VO2 and respiratory exchange ratio were significantly lower, and shoe comfort was significantly greater, in the energy return footwear. Given the relationship between running economy and running performance, these observations indicate that the energy return footwear may be associated with enhanced running performance in comparison to conventional shoes.  相似文献   

13.
Twenty specialist marathon runners and 23 specialist ultra-marathon runners underwent maximal exercise testing to determine the relative value of maximum oxygen consumption (VO2max), peak treadmill running velocity, running velocity at the lactate turnpoint, VO2 at 16 km h-1, % VO2max at 16 km h-1, and running time in other races, for predicting performance in races of 10-90 km. Race time at 10 or 21.1 km was the best predictor of performance at 42.2 km in specialist marathon runners and at 42.2 and 90 km in specialist ultra-marathon runners (r = 0.91-0.97). Peak treadmill running velocity was the best laboratory-measured predictor of performance (r = -0.88(-)-0.94) at all distances in ultra-marathon specialists and at all distances except 42.2 km in marathon specialists. Other predictive variables were running velocity at the lactate turnpoint (r = -0.80(-)-0.92); % VO2max at 16 km h-1 (r = 0.76-0.90) and VO2max (r = 0.55(-)-0.86). Peak blood lactate concentrations (r = 0.68-0.71) and VO2 at 16 km h-1 (r = 0.10-0.61) were less good predictors. These data indicate: (i) that in groups of trained long distance runners, the physiological factors that determine success in races of 10-90 km are the same; thus there may not be variables that predict success uniquely in either 10 km, marathon or ultra-marathon runners, and (ii) that peak treadmill running velocity is at least as good a predictor of running performance as is the lactate turnpoint. Factors that determine the peak treadmill running velocity are not known but are not likely to be related to maximum rates of muscle oxygen utilization.  相似文献   

14.
In sport visual feedback is often used to enhance performance, mostly neglecting the auditory modality. However, athletes produce natural sounds when they move (acoustic reafferences) which they perceive and use to control their movements. We examined the short- and long-term effects of a training intervention on a complex movement by using acoustic reafferences. Natural step sounds produced during hurdling were recorded and played back to the participants immediately before each trial, with an increase (fast group), decrease (slow group), or no manipulation (control group) in the tempo. All groups increased their hurdling performance regarding overall running time, with the slow group showing the best performance development. After a 10-week retention, the fast and slow group further increased performance, whereas the control group declined. The repeated experience with acoustic information associated with the rhythmic pattern of hurdling may have helped developing a cognitive representation of that movement, especially regarding long-term effects.  相似文献   

15.
Abstract

The aim of the study was to compare physiological responses between runners adapted and not adapted to deep water running at maximal intensity and the intensity equivalent to the ventilatory threshold. Seventeen runners, either adapted (n = 10) or not adapted (n = 7) to deep water running, participated in the study. Participants in both groups undertook a maximal treadmill running and deep water running graded exercise test in which cardiorespiratory variables were measured. Interactions between adaptation (adapted vs. non-adapted) and condition (treadmill running vs. deep water running) were analysed. The main effects of adaptation and condition were also analysed in isolation. Runners adapted to deep water running experienced less of a reduction in maximum oxygen consumption ([Vdot]O2max) in deep water running compared with treadmill running than runners not adapted to deep water running. Maximal oxygen consumption, maximal heart rate, maximal ventilation, [Vdot]O2 at the ventilatory threshold, heart rate at the ventilatory threshold, and ventilation at the ventilatory threshold were significantly higher during treadmill than deep water running. Therefore, we conclude that adaptation to deep water running reduces the difference in [Vdot]O2max between the two modalities, possibly due to an increase in muscle recruitment. The results of this study support previous findings of a lower maximal and submaximal physiological response on deep water running for most of the measured parameters.  相似文献   

16.
The correlation between mechanical factors of running and running economy as measured by metabolic cost is a subject of much interest in the study of locomotion. However, no change in running technique has been shown to result in an immediate improvement in running economy on an intra-individual basis. To evaluate the effect of a modified running technique, it is probably necessary that the individual trains with the new technique for a longer period using a feedback system to control the new kinematics. In this study, we examine the feasibility of using visual and auditory feedback to adapt running technique according to a simplistic model of the mechanical cost of running. The model considers only the mechanical work against gravity, which is the product of the magnitude of the vertical displacement of the runner's centre of mass and the step-frequency. In the experiments reported here, 18 trained runners, running at 16 km · h(-1) on a treadmill, were given feedback on these parameters together with indicated target levels. In almost all cases, the runners were able to adjust their technique accordingly.  相似文献   

17.
Research to enhance running performance has led to the design of a leaf spring-structured midsole shoe (LEAF). In treadmill running, it has been shown that LEAF led to an increased running economy and increased stride length (SL) through a horizontal foot shift during stance compared to a standard foam shoe (FOAM). The purpose of this study was to analyse whether (a) these findings can also be observed in overground running and (b) relations exist between spatio-temporal variables and running economy. Ten male long-distance heel-strike runners ran at their individual 2?mmol/l blood lactate speed with LEAF and FOAM in randomized order. Kinematic data were recorded with an inertial measurement unit synchronized with 2D video. Oxygen consumption was measured using an automated metabolic gas analysis system. Blood lactate was collected after each run. The strike pattern was unaffected by LEAF. SL was increased by 0.9?±?1.1?cm (95% CI 0.2 to 1.5; p?=?.040; dz?=?0.76), stride rate (SR) was reduced by ?0.4?±?0.3?strides/min (95% CI ?0.6 to ?0.1; p?=?.029; dz?=?0.82) and oxygen consumption tended to be reduced by 1% (?0.4?±?0.6?ml/min/kg; 95% CI ?0.8 to 0.0; p?=?.082; dz?=?0.62) when running with LEAF compared to FOAM. Changes in oxygen consumption in LEAF were correlated with SL (r?=?0.71; p?=?.022) and SR (r?=??0.68; p?=?.031). It can be concluded that LEAF has the potential to cause small changes in spatio-temporal variables during running. Runners increasing SL and decreasing SR in response to LEAF can achieve small improvements in running economy, which is beneficial in terms of performance.  相似文献   

18.
Fatigue, developed over the course of a run, may cause changes in running kinematics. Training status may influence the effect of fatigue on running kinematics, since well trained, competitive runners are used to running until exhaustion, whereas novice runners are not. This study aimed to determine changes in running kinematics during an exhaustive run in both novice (NOVICE) and competitive (COMP) long-distance runners. About 15 NOVICE and 15 COMP runners performed a treadmill run, until voluntary exhaustion at 3,200 m time trial pace. Joint angles and global trunk and pelvis angles were recorded at the beginning and at the end of the run. In both groups, peak pelvic anterior tilt, pelvic rotation range of motion (both during stance phase) and ankle plantar flexion during swing phase increased after the exhaustive run. There was a significant interaction effect between group and exhaustion for peak forward trunk lean, which increased only in the NOVICE group, and for hip abduction during mid-swing, which increased in NOVICE and decreased in COMP runners. In conclusion, NOVICE runners showed larger kinematic adjustments when exhausted than COMP runners. This may affect their running performance and should be taken into account when assessing a runner’s injury risk.  相似文献   

19.
This study investigated whether male runners improve running performance, running economy, ankle plantar flexor strength, and alter running biomechanics and lower limb bone mineral density when gradually transitioning to using minimalist shoes for 100% of weekly running. The study was a planned follow-up of runners (n?=?50) who transitioned to minimalist or conventional shoes for 35% of weekly structured training in a previous 6-week randomised controlled trial. In that trial, running performance and economy improved more with minimalist shoes than conventional shoes. Runners in each group were instructed to continue running in their allocated shoe during their own preferred training programme for a further 20 weeks while increasing allocated shoe use to 100% of weekly training. At the 20-week follow-up, minimalist shoes did not affect performance (effect size: 0.19; p?=?0.218), running economy (effect size: ≤?0.24; p?≥?0.388), stride rate or length (effect size: ≤?0.12; p?≥?0.550), foot strike (effect size: ≤?0.25; p?≥?0.366), or bone mineral density (effect size: ≤?0.40; p?≥?0.319). Minimalist shoes increased plantar flexor strength more than conventional shoes when runners trained with greater mean weekly training distances (shoe*distance interaction: p?=?0.036). After greater improvements with minimalist shoes during the initial six weeks of a structured training programme, increasing minimalist shoe use from 35% to 100% over 20 weeks, when runners use their own preferred training programme, did not further improve performance, running economy or alter running biomechanics and lower limb bone mineral density. Minimalist shoes improved plantar flexor strength more than conventional shoes in runners with greater weekly training distances.  相似文献   

20.
Field tests of speed and endurance may be used to evaluate the probability of success and to create efficient training strategies for sports. Currently, both invasive and non-invasive methods are used for this purpose. While invasive methods cause some discomfort to subjects, non-invasive methods may employ practices associated with the sport itself. One such method employs the linear relationship between exercise intensity or running speed and distance covered running at that speed represented on a semi-logarithmic scale. The separation of endurance runners into three different groups can be confirmed by different values for the slope coefficient (b) of this linear relation. According to findings among top Czechoslovak endurance runners, supplemented by the data of other authors, the values of coefficient b in middle-distance runners are in the range -2.166 to -1.700, in long-distance runners -1.520 to -1.050 and in marathon runners -0.836 to -0.436. Similarly, a separation of young endurance runners into groups of middle-distance and long-distance runners must be within the range -2.158 to -1.800 and for young long-distance runners -1.700 to -1.300. Based on these findings, the optimum competitive distance for adult athletes can be established in relation to current training status. In young athletes, it is possible to select gifted runners with predispositions for middle-distance and long-distance running. For both groups of athletes, more efficient training methods can be selected to optimize their predispositions for maximal performance.  相似文献   

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