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1.
This study aimed at exploring whether 3D technology enhances tennis decision-making under the conceptual framework of human performance model. A 3 (skill-level: varsity, club, recreational)?×?3 (experimental condition: placebo, weak 3D [W3D], strong 3D [S3D]) between-participant design was used. Allocated to experimental conditions by a skill-level stratified randomization, 105 tennis players judged tennis serve direction from video scenarios and rated their perceptions of enjoyment, flow, and presence during task performance. Results showed that varsity players made more accurate decisions than less skilled ones. Additionally, applying 3D technology to typical video displays reduced tennis players’ decision-making accuracy, although wearing the 3D glasses led to a placebo effect that shortened the decision-making reaction time. The unexpected negative effect of 3D technology on decision-making was possibly due to participants being more familiar to W3D than to S3D, and relatedly, a suboptimal task-technology match. Future directions for advancing this area of research are offered.

Highlights

  • 3D technology augments binocular depth cues to tradition video displays, and thus results in the attainment of more authentic visual representation. This process enhances task fidelity in researching perceptual-cognitive skills in sports.

  • The paper clarified both conceptual and methodological difficulties in testing 3D technology in sports settings. Namely, the nomenclature of video footage (with/without 3D technology) and the possible placebo effect (arising from wearing glasses of 3D technology) merit researchers' attention.

  • Participants varying in level of domain-specific expertise were randomized into viewing conditions using a placebo-controlled design. Measurement consisted of both participants' subjective experience (i.e., presence, flow, and enjoyment) and objective performance (i.e., accuracy and reaction time) in a decision-making task.

  • Findings revealed that wearing glasses of 3D technology resulted in a placebo effect that shortened participants' reaction times in decision-making. Moreover, participants' decision-making accuracy decreased when viewing video scenarios using 3D technology. The findings generated meaningful implications regarding applying 3D technology to sports research.

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2.
The aim of this study was to determine the effects of caffeine ingestion on a ‘preloaded’ protocol that involved cycling for 2?min at a constant rate of 100% maximal power output immediately followed by a 1-min ‘all-out’ effort. Eleven male cyclists completed a ramp test to measure maximal power output. On two other occasions, the participants ingested caffeine (5?mg?·?kg?1) or placebo in a randomized, double-blind procedure. All tests were conducted on the participants' own bicycles using a Kingcycle? test rig. Ratings of perceived exertion (RPE; 6–20 Borg scale) were lower in the caffeine trial by approximately 1 RPE point at 30, 60 and 120?s during the constant rate phase of the preloaded test (P?<0.05). The mean power output during the all-out effort was increased following caffeine ingestion compared with placebo (794±164 vs 750±163?W; P?=?0.05). Blood lactate concentration 4, 5 and 6?min after exercise was also significantly higher by approximately 1?mmol?·?l?1 in the caffeine trial (P?<0.05). These results suggest that high-intensity cycling performance can be increased following moderate caffeine ingestion and that this improvement may be related to a reduction in RPE and an elevation in blood lactate concentration.  相似文献   

3.
Placebo and nocebo effects occur in response to subjective expectations and their subsequent neural actions. Research shows that information shapes expectations that, consequently, influence people’s behaviour. In this study, we examined the effects of a fictive and inert green colour energy drink provided for three groups (n?=?20/group) with different information. The first group was led to expect that the drink augments running performance (positive information), the second group was led to expect that the drink may or may not improve performance (partial-positive information), while the third group was told that earlier research could not demonstrate that the drink improves performance (neutral/control). At baseline, the three groups did not differ in their 200-m sprint performance (p?>?.05). One week later, 20-min immediately after ingesting the drink, all participants again ran 200?m. The positive information group increased its performance by 2.41?s, which was statistically significant (p?<?.001) and also perceived its sprint-time shorter (p?<?.05) than the other two groups. A better performance (0.97?s) that approached but did not reach statistical significance was also noted in the partial-positive information group, and a lesser change (0.72?s) that was statistically not significant was noted in the neutral information control group. These results reveal that drinking an inert liquid, primed with positive information, changes both the actual and the self-perceived time on a 200-m sprint. The current findings also suggest that the level of certainty of the information might be linked to the magnitude of change in performance.  相似文献   

4.
Abstract

Carbohydrate (CHO) mouth rinse has been shown to improve time trial performance. Although the exact mechanism remains un-established, research postulates that there are oral cavity receptors which increase neural drive. Increasing the duration of the mouth rinse could potentially increase stimulation of these receptors. The aim of the current investigation was to determine whether the duration of mouth rinse with 6.4% CHO affected 30-min self-selected cycling performance. Eleven male participants (age =24.1±3.9 years) performed three 30-min self-paced trials. On one occasion water was given as a mouth rinse for 5 s without being ingested placebo (PLA), on the other two occasions a 6.4% CHO solution was given for 5 and 10 s. Distance cycled, heart rate, ratings of perceived exertion, cadence, speed and power were recorded throughout all trials. The main findings were that distance cycled during the 10-s mouth rinse trial (20.4±2.3 km) was significantly greater compared to the PLA trial (19.2±2.2 km; P<0.01). There was no difference between the 5- and 10-s trials (P=0.15). However, 10 out of 11 participants cycled further during the 5-s trial compared to PLA, and eight cycled further during the 10-s trial compared to the 5 s. In conclusion, although there was an improvement in distance cycled with the 5-s mouth rinse compared to the PLA it was only significant with 10 s suggesting a dose response to the duration of mouth rinse.  相似文献   

5.
Abstract

The efficacy of caffeine ingestion in enhancing aerobic performance is well established. However, despite suggestions that caffeine may enhance resistance exercise performance, research is equivocal on the effect of acute caffeine ingestion on resistance exercise performance. It has also been suggested that dampened perception of perceived exertion and pain perception might be an explanation for any possible enhancement of resistance exercise performance due to caffeine ingestion. Therefore, the aim of this study was to examine the acute effect of caffeine ingestion on repetitions to failure, rating of perceived exertion (RPE) and muscle pain perception during resistance exercise to failure. Eleven resistance trained individuals (9 males, 2 females, mean age±SD=26.4±6.4 years), took part in this double-blind, randomised cross-over experimental study whereby they ingested a caffeinated (5 mg kg?1) or placebo solution 60 minutes before completing a bout of resistance exercise. Experimental conditions were separated by at least 48 hours. Resistance exercise sessions consisted of bench press, deadlift, prone row and back squat exercise to failure at an intensity of 60% 1 repetition maximum. Results indicated that participants completed significantly greater repetitions to failure, irrespective of exercise, in the presence of caffeine (p=0.0001). Mean±S.D of repetitions to failure was 19.6±3.7 and 18.5±4.1 in caffeine and placebo conditions, respectively. There were no differences in peak heart rate or peak blood lactate values across conditions (both p >0.05). RPE was significantly lower in the caffeine compared to the placebo condition (p=0.03) and was significantly higher during lower body exercises compared to upper body exercises irrespective of substance ingested (p=0.0001). For muscle pain perception, a significant condition by exercise interaction (p=0.027) revealed that muscle pain perception was lower in the caffeine condition, irrespective of exercise. With caffeine, pain perception was significantly higher in the deadlift and back squat compared to the bench press. However, with placebo, pain perception was significantly higher for the deadlift and back squat compared to the prone row only. Therefore, acute caffeine ingestion not only enhances resistance exercise performance to failure but also reduces perception of exertion and muscle pain.  相似文献   

6.
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   

7.
Abstract

The purpose of the present study was to determine the effects of 10-in [025–m] versus 16-in [0.41-m] wheelchair handrims on cardiorespiratory and psychophysiological exercise responses during wheelchair propulsion at selected velocities. Fifteen male paraplegics (27.0 ± 5.5 yrs) performed three discontinuous exercise tests (ACE = arm crank ergometer; WERG = wheelchair roller ergometer) and two 1600-m performance-based track trials (TRACK) under simulated race conditions. There were no significant differences in HR, VO2, VE, HLa, or category-ratio ratings of perceived exertion (RPE) using different handrims during wheelchair propulsion at 4 km-h1. In contrast, at 8 km-h?1 subjects demonstrated a 13% lower steady state VO2 (p < .05) using the 10-in handrims, coincident with a 23% lower VE Steady state HR during WERG at 8 km-h?1 using the 10-in (124.4 ± 39 b.min?1) or 16-in (130.6 ± 4.6 b.min?1) handrims were not significantly different. There were also no significant differences between ACE or WERG conditions during maximal effort for VO2 or VE. However, HRpeak during ACE was 7% higher than HRpeak during WERG16 (183 ± 15 b.min?1 vs. 171 ± 12 b.min?1, p < .05), and whole blood HLa during ACE was also significantly higher (by 2.3-2.5 mmol; p < .05) compared to WERG. There were no significant differences for HR, performance time, or RPE between trials using different handrim diameters during the 1600-m event. In contrast, HLa was significantly lower using smaller handrims (9.9 mmol) compared with larger handrims (11.3 mmol), paralleling a similar difference in the laboratory. Although these data demonstrated few significant differences of physiologic responses between trials using different handrims, there was a tendency for a lower metabolic stress using the smaller handrims.  相似文献   

8.
Twelve elite players from an English Super League club consented to participate in the present study using portable global positioning system (GPS) devices to assess position-specific demands. Distances covered at low-intensity running, moderate-intensity running, high-intensity running, very high-intensity running, and total distance were significantly (P < 0.05) lower in forwards compared with outside backs and adjustables. Metres per minute was higher in adjustables and forwards, owing to higher values for relative distance in medium-intensity running and a rise in high-intensity running from previous absolute values. Sprint distance, sprint frequency, and peak speed were higher in outside backs than both adjustables and forwards. A moderate, significant correlation (r = 0.62, P = 0.001) was apparent between session ratings of perceived exertion and summated heart rate. Results support the requirement for position-specific conditioning and provide preliminary evidence for the use of session ratings of perceived exertion as a measure of match load.  相似文献   

9.
We examined the effects of time of day on a cycling time trial with and without a prolonged warm-up, among cyclists who tended towards being high in “morningness”. Eight male cyclists (mean?±?s: age = 24.9?±?3.5 years, peak power output = 319?±?34?W, chronotype = 39?±?6 units) completed a 16.1-km time trial without a substantial warm-up at both 07:30 and 17:30?h. The time trial was also completed at both times of day after a 25-min warm-up at 60% of peak power. Power output, heart rate, intra-aural temperature and category ratings of perceived exertion (CR-10) were measured throughout the time trial. Post-test blood lactate concentration was also recorded. Warm-up generally improved time trial performance at both times of day (95% CI for improvement = 0 to 30?s), but mean cycling time was still significantly slower at 07:30?h than at 17:30?h after the warm-up (95% CI for difference = 33 to 66?s). Intra-aural temperature increased as the time trial progressed (P <?0.0005) and was significantly higher throughout the time trials at 17:30?h (P = 0.001), irrespective of whether the cyclists performed a warm-up or not. Blood lactate concentration after the time trial was lowest at 07:30?h without a warm-up (P = 0.02). No effects of time of day or warm-up were found for CR-10 or heart rate responses during the time trial. These results suggest that 16.1-km cycling performance is worse in the morning than in the afternoon, even with athletes who tend towards ‘morningness’, and who perform a vigorous 25-min warm-up. Diurnal variation in cycling performance is, therefore, relatively robust to some external and behavioural factors.  相似文献   

10.
Carbohydrate mouth rinse (CMR) is a novel method proposed to enhance endurance performance lasting ≤ 60 min. The current study examined the influence of CMR on anaerobic performance tasks in 11 collegiate female soccer players after an overnight fast. Athletes completed two experimental sessions, during which carbohydrate (CHO; 6% maltodextrin) or taste- and colour-matched placebo (PLA) mouth-rinse solutions were administered in a counterbalanced, double-blinded design. Three rounds of a 5-min scrimmage bout and series of performance tests including a single countermovement vertical jump (1VJ), a set of four consecutive vertical jumps, a 72-m shuttle run (SR72) and 18-m sprint comprised each trial. Thirst sensation (TS), session TS, ratings of perceived exertion (RPE) and session RPE were assessed as secondary outcomes. The first SR72 approached significance (p = 0.069), but no significant between-trials differences were observed for any of the mean performance tasks. The highest 1VJ scores did not differ for the first (CHO = 47.3 ± 3.4, PLA = 47.7 ± 3.5 cm; p = 0.43), second (CHO = 48.0 ± 4.1, PLA = 47.9 ± 3.5 cm; p = 0.82) or third bout (CHO = 47.4 ± 3.9, PLA = 48.1 ± 3.9 cm; p = 0.26). TS approached significance (p = 0.053) during the first bout. No significant differences (p > 0.05) were found for any of the perceptual variables. Current results fail to support ergogenic influence of CMR on anaerobic performance tasks in collegiate female athletes.  相似文献   

11.
Abstract

College students (N = 72) took a four-minute test of addition on two separate days, once preceded by an exhausting treadmill run and once without prior exertion. Scores were recorded for speed and accuracy for each minute and for the total four minutes. It was found that the exertion had a significant negative effect on accuracy for the total four minutes as well as for the second and fourth minute. No significant effect of exertion on speed was obtained. When control and experimental conditions were considered together a significant trend in favor of high fitness subjects was found on speed of addition. Significant differences in favor of medium and high fitness subjects were found on accuracy of addition.  相似文献   

12.
A 30‐s ‘all‐out’ power protocol was studied in four groups of racing cyclists including internationals (n = 8), Category 1 (n = 10), Category 2 (n = 15) and Category 3 (n = 11). Following warm‐up each subject completed five trials interspersed by 3 min of low intensity exercise on an ergowheel racing cycle ergometry system at a power output of 15 W kg–1 body weight, generated at 130 rev min–1. Temporal indices of performance included delay time (DT) to achieve the power criterion, total time (TT) of the maintenance of the power criterion and the ratio of TT/DT. ‘Explosive’ leg strength was assessed from a vertical jump. The results indicated that international and Category 1 cyclists had lower DT (2.2 ± 0.1s and 2.1 +0.0s, respectively; P<0.05), higher TT (28.1 ±0.7s and 27.0+0.7s, respectively; P<0.05) and elevated TT/DT (12.8 and 12.9, respectively; P<0.01). ‘Explosive’ leg strength was also higher (P<0.05) in the internationals than in the other groups of cyclists. The protocol provides a sport‐related method for the assessment of short term endurance performance ability in racing cyclists which may be of value in identifying the anaerobic capability of individual cyclists.  相似文献   

13.
This study examined the effect of early evening high-intensity training on the sleep of elite male youth soccer players (n = 12) using wrist actigraphy. High-intensity training (TRAIN) nights were compared with a home environment (HOME) condition, created by averaging sleep variables on the night before and after TRAIN nights. Additionally, after TRAIN athletes alternately used cold water immersion (TRAIN+CWI) or none, to assess whether cold water immersion (CWI) had any impact on sleep quality and quantity. Ratings of perceived exertion, fatigue and recovery were recorded after training. Actigraphy sleep measures were bedtime, wake time, sleep duration, sleep onset latency, sleep efficiency and wake after sleep onset. Self-rated scores of sleepiness at bedtime and wake, plus overall sleep quality were also recorded. Only fatigue ratings were higher in TRAIN compared to TRAIN+CWI at bedtime, there were no other differences in training data. Both TRAIN and TRAIN+CWI conditions had significant later (07:45 ± 1:09 h p < 0.01 and 07:34 ± 1:20 h p = 0.01) wake times than HOME (06:44 ± 0:41 h). The TRAIN condition had a significantly higher (7 ± 2; p < 0.01) rating of sleepiness at bedtime compared to HOME (6 ± 1), but no further differences were found in any of the sleep (actigraphy and self-reported) measures. Across all conditions, time spent asleep was ～7:30 (±0:52) h:min and sleep efficiency was ～89% (±6.1). In conclusion, early evening high-intensity training had no impact on subsequent sleep quality and quantity, nor was there any effect on sleep after performing CWI post-training.  相似文献   

14.
The purpose of the present study was to determine the effects of 10-in [0.25-m] versus 16-in [0.41-m] wheelchair handrims on cardiorespiratory and psychophysiological exercise responses during wheelchair propulsion at selected velocities. Fifteen male paraplegics (27.0 +/- 5.5 yrs) performed three discontinuous exercise tests (ACE = arm crank ergometer; WERG = wheelchair roller ergometer) and two 1600-m performance-based track trials (TRACK) under simulated race conditions. There were no significant differences in HR, VO2, VE, HLa, or category-ratio ratings of perceived exertion (RPE) using different handrims during wheelchair propulsion at 4 km.h-1. In contrast, at 8 km.h-1 subjects demonstrated a 13% lower steady state VO2 (p less than .05) using the 10-in handrims, coincident with a 23% lower VE. Steady state HR during WERG at 8 km.h-1 using the 10-in (124.4 +/- 3.9 b.min-1) or 16-in (130.6 +/- 4.6 b.min-1) handrims were not significantly different. There were also no significant differences between ACE or WERG conditions during maximal effort for VO2 or VE. However, HRpeak during ACE was 7% higher than HRpeak during WERG16 (183 +/- 15 b.min-1 vs. 171 +/- 12 b.min-1, p less than .05), and whole blood HLa during ACE was also significantly higher (by 2.3-2.5 mmol; p less than .05) compared to WERG. There were no significant differences for HR, performance time, or RPE between trials using different handrim diameters during the 1600-m event.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

15.
In contrast with the Netherlands’ status as a sports nation, academic articles on Dutch sports history are scarce. In this paper, we would like to establish a ‘textual’ basis for further research. By means of a large-scale digital analysis, we have been able to depict important phases in the Dutch ‘sportification process’. Sport gradually infiltrated Dutch society: first it was mentioned as an English word in bilingual dictionaries, translated literature and ego documents. Then, English sports were described in recreational education books. Indeed, from 1845 onwards, English teachers at Dutch elite schools played an important role in the actual practising of English sports such as cricket, hockey and football. Together with the founding of sports clubs, specific sports manuals were published. Finally, via the introduction of sports sections in general newspapers, sport (as term) was widely diffused in society. Hence, in 1910, Luitje Van Der Wal was the first to translate the English word sport as ‘sport’ in K. Ten Bruggencate’s Engelsch Woordenboek. To be sure, this sportification process did not please everyone. There were warnings about the negative aspects that the adoption of English sports would create. Nonetheless, even traditional Dutch activities became sportified in a modern way.  相似文献   

16.
Medical care in sport comprises a variety of treatments, from scientifically proven biomedicine to complementary and alternative medicine. Information and knowledge about these diverse treatment options is spread by different sources. Thus, athletes encounter information of varying content, quality and background. This exploratory pilot study addresses athletes' medical opinions, their health-related information seeking behaviour and the knowledge sources they utilise. Questionnaires were used to examine n = 110 German athletes (nmale = 69, nfemale = 41; meanage = 24.28 ± 4.97 years) at high performance levels (national team and/or European championship and/or World championship n = 22; first national league and/or German championship n = 51, second national league and/or State championship n = 37) from various Olympic sports. A cluster analysis regarding the athletes' attitudes towards sport medicine exhibited four different types of athletes: ‘the autonomous athlete’, ‘the open-minded athlete’, ‘the functionalistic athlete’ and ‘the conservative athlete’. In general, our findings show that the most used and trusted information sources are physicians and physiotherapists. However, medical information is trusted the most if it is experience- and field-tested, and comes from the athletes' sport-specific network. Our findings also suggest that professional medical knowledge management in competitive sport is needed.  相似文献   

17.
Abstract

The purpose of this study was to describe the mechanical characteristics of a trampoline circus act and its individual tracks performed in training and shows using a tri-axial accelerometer. A track is an artist’s specific role within a choreographed act. Seven male acrobats performed their trampoline act during training and shows while wearing a triaxial accelerometer and reported ratings of perceived exertion (RPE) after each trial. Average acceleration (AVG), root mean square (RMS), root mean to the fourth (RM4), time spent in specific acceleration ranges and RPE were measured/recorded from training and show acts. Paired t-tests compared dependent variables between training and show. Acceleration AVG, RMS and RM4 were significantly higher (p < 0.05) in training than show. RPE was significantly higher (p < 0.05) in show than training. No significant differences existed in time spent in any of the acceleration ranges between training and show. GPS devices have been used to manage workloads in field sports but are inoperable in theatres. But, inertial measurements may be an effective alternative to describe mechanical demands in theatre or arena environments. Wearable technology may be useful to coaches to improve understanding of track demands to manage artist workloads.  相似文献   

18.
ABSTRACT

Though highly popular, degree-level sports coaching qualifications are in their infancy, and it remains that ‘an individual intending to become an accredited coaching practitioner can only do so by undertaking their sport's national governing body (NGB) coaching award(s)’ [Nelson et al., 2006, p. 254. Formal, nonformal and informal coach learning: A holistic conceptualisation. International Journal of Sports Science & Coaching, 1(3), 247–259]. Consequently, little is known about the development of HE sports coaching students’ employability. This study critically investigates sports coaching students’ degree-study motives, development of employability skills and perceptions of career prospects as graduates. Survey data and follow-up interviews from two U.K. post-92 universities reveal tensions between liberal and vocational philosophies of university education and concerns about the graduate labour market. Critical incidents and missed opportunities in students’ development of key skills for coaching during and outside of university are also discussed.  相似文献   

19.
Background: Previous research on physical education (PE) teaching practice indicates that an exercise physiology discourse has assumed a dominant position within the field. Research shows that PE teachers are likely to emphasise physical fitness training in their teaching, and PE teachers seem to appreciate pupils who show high levels of physical exertion.

Purposes: Our aim is to examine how vigorous activity/exercise is represented in the practice of PE teaching. We will also examine teaching as a discursive practice, and thereby contribute to a critical perspective on PE pedagogy.

Research design: This study was conducted in four upper secondary schools in Oslo, Norway. Data material was produced through fieldwork, during which we observed 92 PE lessons. Additionally, we conducted qualitative interviews with the eight teachers who participated in the study. Our methodological framework was discourse analysis.

Findings: Our material shows that vigorous activity plays a complex role in PE class: it can be beneficial, but it can also be punitive. The PE teachers we observed drew on an exercise physiology discourse to portray vigorous activity/exercise as beneficial and valuable to the promotion of pupils’ physical fitness and health. However, the teachers also drew on a military discourse when assigning vigorous activity to rebuke a disobedient pupil. The teachers also introduced vigorous activity in the form of additional exercise ‘punishment’, which they assigned to losers in competitive activities. In these instances, the teachers drew on exercise physiology and sports discourses. Thus, we identified how vigorous activity changed value according to context, and discuss how teachers’ use of vigorous activity as punishment can seem paradoxical in a PE setting.

Conclusion and recommendation: Our study indicates that, rather than adhering to modern educational practices, PE is rooted in ideas and practices derived from military, sports and exercise physiology discourses. PE teachers inculcated with these discourses have limited ability to discern the paradox of assigning vigorous exercise to their pupils as both a high-value activity and a punishment. PE Teacher Education should therefore problematise how teaching practice is influenced by these discourses, and facilitate discussions on how such discourses constitute PE.  相似文献   


20.
Abstract

It is not known if ergogenic effects of caffeine ingestion in athletic groups occur in the sedentary. To investigate this, we used a counterbalanced, double-blind, crossover design to examine the effects of caffeine ingestion (6 mg · kg?1 body-mass) on exercise performance, substrate utilisation and perceived exertion during 30 minutes of self-paced stationary cycling in sedentary men. Participants performed two trials, one week apart, after ingestion of either caffeine or placebo one hour before exercise. Participants were instructed to cycle as quickly as they could during each trial. External work (J · kg?1) after caffeine ingestion was greater than after placebo (P = 0.001, effect size [ES] = 0.3). Further, heart rate, oxygen uptake and energy expenditure during exercise were greater after caffeine ingestion (P = 0.031, ES = 0.4; P = 0.009, ES = 0.3 and P = 0.018, ES = 0.3; respectively), whereas ratings of perceived exertion and respiratory exchange ratio values did not differ between trials (P = 0.877, ES = 0.1; P = 0.760, ES = 0.1; respectively). The ability to do more exercise after caffeine ingestion, without an accompanying increase in effort sensation, could motivate sedentary men to participate in exercise more often and so reduce adverse effects of inactivity on health.  相似文献   

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