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1.
Although much research has examined the relationship between exercise and affect, few studies have considered the effects of exercise bouts of different durations and few researchers have questioned the longer term effects that might be associated with acute exercise. The aim of this study was to compare the effects of the standard health recommended exercise duration of 30?min with a shorter (15?min) bout of exercise upon individuals' affect scores both during and after exercise. Twenty-three (mean age 22.4 years) physically active participants engaged in two counterbalanced cycle ergometer exercise conditions for 15?min (short bout) and 30?min (moderate bout). The participants completed the Subjective Exercise Experience Scale before, during, 5?min, 30 mins, 1?h and 2?h after both exercise conditions. A series of 2 × 6 within-participant repeated-measures analyses of variance for positive well-being (P?<0.01), psychological distress (P?<0.01) and fatigue (P?<0.01) scores revealed significant time main effects, with improved scores over time. No significant differences were noted between the 15-min and 30-min exercise bouts. These results indicate that positive affective responses are experienced by exercisers after relatively short bouts of acute exercise and these effects can still be evident some time later.  相似文献   

2.
Abstract

The increased energy demand that occurs with incremental exercise intensity is met by increases in the oxidation of both endogenous fat and carbohydrate stores up to an intensity of ~70% V˙O2max in trained individuals. However, when exercise intensity increases beyond this workload, fat oxidation rates decline, both from a relative and absolute perspective. As endogenous glycogen use is accelerated, glycogen stores can become depleted, ultimately resulting in fatigue and the inability to maintain high intensity, submaximal exercise (>70% V˙O2max). Despite a considerable accumulation of knowledge that has been gained over the past half century, the precise mechanism(s) regulating muscle fuel selection and underpinning the aforementioned decline in fat oxidation remain largely unclear. A greater understanding would undoubtedly lead to novel strategies to increase fat utilization and, as such, improve exercise capacity. The present review primarily addresses one of the most prominent theories to explain the phenomenon of diminished fat oxidation during high intensity, submaximal exercise; a reduced availability of muscle free carnitine for mitochondrial fat translocation. This is discussed in the light of recent work in this area taking advantage of the discovery that muscle carnitine content can be increased in vivo in humans. Furthermore, the evidence supporting the recently proposed theory that reduced muscle co-enzyme A availability to several key enzymes in the fat oxidation pathway may also exert a degree of control over muscle fuel selection during exercise is also considered. Strong correlational evidence exists that muscle free carnitine availability is likely to be a key limiting factor to fat oxidation during high intensity, submaximal exercise. However, it is concluded that further intervention studies manipulating the muscle carnitine pool in humans are required to establish a direct causal role. In addition, it is concluded that while a depletion of muscle coenzyme A availability during exercise also offers a viable mechanism for impairing fat oxidation, at present, this remains speculative.  相似文献   

3.
I model average running speed on distances from 5000 m to the marathon as a function of age, distance and sex. Using data on US age-dependent road-racing records, I simulate optimal performance for ages ranging from 3 to 95 years. The results of the correlation between running speed and age are in line with medical results on the relation between age and maximal oxygen uptake. The results show that official track and field age-grading overestimates human performance at older ages.  相似文献   

4.
This study examined the effects of different work?–?rest durations during 40?min intermittent treadmill exercise and subsequent running performance. Eight males (mean?±?s: age 24.3?±?2.0 years, body mass 79.4?±?7.0?kg, height 1.77?±?0.05?m) undertook intermittent exercise involving repeated sprints at 120% of the speed at which maximal oxygen uptake (v-[Vdot]O2max) was attained with passive recovery between each one. The work?–?rest ratio was constant at 1:1.5 with trials involving short (6:9?s), medium (12:18?s) or long (24:36?s) work?–?rest durations. Each trial was followed by a performance run to volitional exhaustion at 150% v-[Vdot]O2max. After 40?min, mean exercise intensity was greater during the long (68.4?±?9.3%) than the short work?–?rest trial (54.9?±?8.1% [Vdot]O2max; P?<?0.05). Blood lactate concentration at 10?min was higher in the long and medium than in the short work?–?rest trial (6.1?±?0.8, 5.2?±?0.9, 4.5?±?1.3?mmol?·?l?1, respectively; P?<?0.05). The respiratory exchange ratio was consistently higher during the long than during the medium and short work?–?rest trials (P <?0.05). Plasma glucose concentration was higher in the long and medium than in the short work?–?rest trial after 40?min of exercise (5.6?±?0.1, 6.6?±?0.2 and 5.3?±?0.5?mmol?·?l?1, respectively; P?<?0.05). No differences were observed between trials for performance time (72.7?±?14.9, 63.2?±?13.2, 57.6?±?13.5?s for the short, medium and long work?–?rest trial, respectively; P = 0.17), although a relationship between performance time and 40?min plasma glucose was observed (P?<?0.05). The results show that 40?min of intermittent exercise involving long and medium work?–?rest durations elicits greater physiological strain and carbohydrate utilization than the same amount of intermittent exercise undertaken with a short work?–?rest duration.  相似文献   

5.
This study investigated the effects of combined sleep deprivation and strenuous exercise on cognitive and neurobehavioral performance among long-distance runners completing one of the most difficult ultramarathons in the world. Seventeen runners participated. Each had a wrist-worn actigraph throughout the race to record their sleep time. In addition, each individual’s performance in 10-min response-time tests before and after the race was recorded and a questionnaire enabled participants to report any difficulties they experienced during the competition. During race completion times of 27 to 44 h, combined acute lack of sleep (12 ± 17 min of rest during the race) and strenuous exercise (168.0 km) had marked adverse effects on cognitive performances ranging from mere lengthening of response time to serious symptoms such as visual hallucinations. This study suggests that regardless of rest duration and time in race, cognitive performances of ultramarathoners are adversely affected.  相似文献   

6.
BackgroundA goal of 10,000 steps per day is widely advocated, but there is little evidence to support that goal. Our purpose was to examine the dose–response relationships between step count and all-cause mortality and cardiovascular disease risk.MethodsCochrane Central Register of Controlled Trials, EMBASE, OVID, PubMed, Scopus, and Web of Science databases were systematically searched for studies published before July 9, 2021, that evaluated the association between daily steps and at least 1 outcome.ResultsSixteen publications (12 related to all-cause mortality, 5 related to cardiovascular disease; and 1 article contained 2 outcomes: both all-cause death and cardiovascular events) were eligible for inclusion in the meta-analysis. There was evidence of a nonlinear dose–response relationship between step count and risk of all-cause mortality or cardiovascular disease (p = 0.002 and p = 0.014 for nonlinearity, respectively). When we restricted the analyses to accelerometer-based studies, the third quartile had a 40.36% lower risk of all-cause mortality and a 35.05% lower risk of cardiovascular event than the first quartile (all-cause mortality: Q1 = 4183 steps/day, Q3 = 8959 steps/day; cardiovascular event: Q1 = 3500 steps/day, Q3 = 9500 steps/day; respectively).ConclusionOur meta-analysis suggests inverse associations between higher step count and risk of premature death and cardiovascular events in middle-aged and older adults, with nonlinear dose–response patterns.  相似文献   

7.
ABSTRACT

We assessed the intraocular pressure (IOP) behaviour during a 1-minute period of isometric physical effort and the immediate 1-minute of recovery in the mid-thigh clean pull and squat exercises at three different intensities. Twenty physically active individuals performed the isometric mid-thigh clean pull and squat exercises at three intensities (0% [low-intensity], 25% [medium-intensity] and 50% [high-intensity] of the maximum isometric force). IOP was semi-continuously measured by rebound tonometry. There was a statistically significant effect of exercise intensity on IOP (p < 0.001, ?p² = 0.416), observing that IOP increments were positively associated with exercise intensity. The mid-thigh clean pull and squat exercises did not demonstrate differences (p = 0.510), and also, no differences were observed between men and women (p = 0.683). The IOP changes during the isometric physical effort showed a positive linear behaviour in all conditions (r = 0.70 to 0.96). IOP returned to baseline levels after 8 seconds of recovery. Our data showed a progressive and instantaneous IOP increment during isometric exercise, which was positively associated with exercise intensity. IOP changes were independent on the type of exercise and participant´s sex. After exercise, IOP rapidly (≈ 8 seconds) returned to baseline levels.  相似文献   

8.
ABSTRACT

Research in aerobic exercise has linked the affective responses (pleasure–displeasure) experienced during exercise to future exercise participation. While this is yet to be confirmed in anaerobic activities, it can be inferred that making resistance exercise (RE) more psychologically rewarding is an important consideration. The purpose of this article is to review the acute effects of RE on affect, anxiety, and mood and to draw conclusions on how to maximize feelings of pleasure in an effort to increase rates of participation. This review provides evidence to support lower training volumes performed at low to moderate intensities (50–70% 1RM) with long inter-set rest intervals (90–150 s). Additional recommendations are provided based on physiological and theoretical support, but there is a strong need for more research on the affective experience of RE.  相似文献   

9.
A model for systematic changes in patterns of inter-individual variation in affective responses to physical activity of varying intensities is presented, as a conceptual alternative to the search for a global dose?–?response curve. It is theorized that trends towards universality will emerge in response to activities that are either generally adaptive, such as moderate walking, or generally maladaptive, such as strenuous running that requires anaerobic metabolism and precludes the maintenance of a physiological steady state. At the former intensity the dominant response will be pleasure, whereas at the latter intensity the dominant response will be displeasure. In contrast, affective responses will be highly variable, involving pleasure or displeasure, when the intensity of physical activity approximates the transition from aerobic to anaerobic metabolism, since activity performed at this intensity entails a trade-off between benefits and risks. Preliminary evidence in support of this model is presented, based on a reanalysis of data from a series of studies.  相似文献   

10.
We have previously argued that there may actually be no significant eccentric, but rather predominantly an isometric action of the hamstring muscle fibres during the swing phase of high-speed running when the attachment points of the hamstrings are moving apart. Based on this we suggested that isometric rather than eccentric exercises are a more specific way of conditioning the hamstrings for high-speed running. In this review we argue that some of the presumed beneficial adaptations following eccentric training may actually not be related to the eccentric muscle fibre action, but to other factors such as exercise intensity. Furthermore, we discuss several disadvantages associated with commonly used eccentric hamstring exercises. Subsequently, we argue that high-intensity isometric exercises in which the series elastic element stretches and recoils may be equally or even more effective at conditioning the hamstrings for high-speed running, since they also avoid some of the negative side effects associated with eccentric training. We provide several criteria that exercises should fulfil to effectively condition the hamstrings for high-speed running. Adherence to these criteria will guarantee specificity with regards to hamstrings functioning during running. Practical examples of isometric exercises that likely meet several criteria are provided.  相似文献   

11.
12.
Abstract

Twelve healthy participants performed two identical high-intensity 40 km cycling trials (morning and evening) under controlled laboratory conditions. Echocardiograms and venous blood samples were collected before and after each exercise bout. Cardiac electro-mechanical-delay (cEMD) was measured as QRS-complex onset to peak systolic (S’) and early diastolic (E’) tissue velocities. Myocardial strain and strain rates were assessed in longitudinal, circumferential and radial planes at the left ventricular apex and base. Cardiac troponin I (cTnI) and N-terminal Pro-Brain Natriuretic Peptide (NT-proBNP) were assessed as biomarkers of cardiomyocyte damage and wall stress. cEMD was lengthened after both morning (S’: 160 ± 30 vs. 193 ± 27; E’: 478 ± 60 vs. 620 ± 87, P < 0.05) and evening (S’: 155 ± 29 vs. 195 ± 31; E’: 488 ± 42 vs. 614 ± 61, P < 0.05) trials. A reduction in peak S’ (morning: 6.96 ± 1.12 vs. 6.66 ± 0.89; evening: 7.09 ± 0.94 vs. 7.02 ± 0.76) was correlated with cEMD (r = ?0.335, P < 0.05). Peak longitudinal strain was reduced, atrial strain rates were sporadically increased in both trials post-cycling. cTnI was elevated in only two participants (0.04 µg · L?1, 0.03 µg · L?1), whilst NT-proBNP was below the clinical cut-off point in all participants. Prolonged-cycling resulted in a lengthening of cEMD, small changes in aspects of left ventricular deformation and sporadic increases in cardiac biomarkers. None of these effects were moderated by time-of-day.  相似文献   

13.
Background: The aim of this systematic review was to investigate the association of different components of physical fitness on cognitive performance (CP) and academic performance (AP) in adolescents, taking into account potential confounders. Method: Studies were identified in four databases (Pubmed, SportDiscus, Web of Science, and ProQuest) from January 2005 through to January 2015. A total of 21 articles met the inclusion criteria. Results: 8 studies showed association between physical fitness and CP, and 11 studies with AP. Cardiorespiratory fitness, speed-agility, motor coordination, and perceptual-motor skill are the highest measures associated with CP and AP. However, the findings on strength and flexibility are unclear. Finally, 62% of the 21 studies used confounders. The most controlled confounder were socioeconomic status, fatness, pubertal status, sex, and age. Conclusion: Fitness is associated with higher CP and AP. More research is needed in order to understand the causes of the differential effect of physical fitness components on CP and AP.  相似文献   

14.
Background: During the socialization process when becoming a physical education (PE) teacher, the knowledge, perceptions and expectations of what it means to work as a teacher are developed. In this socialization, the initial acculturation phase is shown to be of the most importance, since individual PE teachers’ experiences during this phase are shown to have a long-lasting influence on their approach to and perception of the subject and the profession. Furthermore, research shows that most physical education teacher education (PETE) programmes are ineffective in altering these initial perceptions and beliefs during the programme. This inertia to change may resemble Bourdieu’s concept of habitus.

Purpose: The purpose of this study was to analyse the background of PE preservice teacher students (PSTs) and examine their embodied perceptions and beliefs related to the subject and profession when they enrol. Specifically, the study focuses on their background characteristics, perceptions of PE and PE teachers, and whether their background and perceptions changed between 2005 and 2016.

Method: This study draws on a web-based questionnaire completed by 224 students (90 women and 134 men) enrolled in the PETE programme at a major university in Sweden between 2005 and 2016. The questionnaire used in this study addressed the PSTs’ experiences, views, beliefs and perceptions of PE and the PE profession, and it was completed during the first semester of respective students’ PE subject studies.

Findings: PE PSTs are a homogeneous group of students with similar backgrounds, experiences and perceptions of PE and their future profession as PE teachers. Participants suggested that important characteristics for a good PE teacher include possessing subject knowledge, having pedagogical competence and being considerate. A good PE lesson should be fun and inspiring, consist of physical activity and be adapted to all. Important goals for PE are to develop pupils’ character and promote healthy behaviours. The PSTs’ background characteristics and perceptions do not seem to have changed during the studied period, in spite of the fact that the structure of the PETE programme did change.

Conclusions: The homogeneous background among PSTs, with vast experience of sport and physical activity, implies that they will interact and engage with students with similar backgrounds and perceptions (i.e. habitus) during PETE. This may limit the potential influence of PETE and fail to prepare PSTs for the demands of their future profession. However, if the influences of acculturation were accounted for during PETE, the programmes could be better designed and better prepare PSTs for their future profession.  相似文献   


15.
In view of the persistence of health inequalities and declines in leisure-sport participation over the life course, several quantitative investigations have explored the links between participation and other leisure activities, which have their foundations in childhood and youth, as a means of understanding adults’ health behaviours. This paper presents new qualitative evidence to examine the largely under-explored relationship between leisure-sport participation and health within the context of educational transitions among a sample of 30–35-year-olds in north-west England. Drawing on semi-structured interviews conducted with 19 participants between July and August 2009, the paper illuminates the differential impact that gender and social class had on sports participation, and other health-related behaviours (e.g. drinking and smoking), among different groups of adults during the inherently transitional life-stage of youth. The findings suggest that while significant, the length of time spent in education and the differential educational experiences recalled by adults cannot adequately explain the observed differences in health and leisure-sport participation. The major sources of difference, while associated with educational transitions, appeared to lie instead in the broader inequalities that characterized adults’ lives and it is argued that simply enhancing leisure-sport participation and individual lifestyle change, as a means of health promotion, is a futile endeavour that does little to tackle the socio-economic structural determinants of health. We conclude by suggesting that until this is recognized by government and those both inside and outside of the health and sport policy communities, stubborn differences in leisure-sport participation rates and health inequalities—that have their foundations in childhood and youth, but extend over the life course—are likely to remain intact, and the unequal lives people currently lead are likely to become even more unequal in the future.  相似文献   

16.
Scapular dyskinesis is the term used to describe changes in the positioning or movement of the scapula. Such dysfunction is associated with changes in the activation of the scapular muscles. However, the influence of the axial muscles on the scapular muscles activity of subjects with scapular dyskinesis is unknown. This study aimed to compare the electromyography (EMG) activity of periscapular muscles and its correlation with the external oblique muscle during the execution of push-up performed in different surfaces, in volunteers with and without scapular dyskinesis. Thirty-six men, divided in two groups (control and dyskinesis), performed push-up on stable and unstable surface. The EMG activity of serratus anterior (SA_5th and SA_7th fibers), upper (UT) and lower (LT) trapezius, external oblique (EO) was recorded during execution of each task condition. Statistical analyzes were performed using two way ANOVA repeated measures and Pearson correlation. It was observed effect of interaction between factors, being evidenced increased activity of UT, SA_7th and OE for the control group and decreased activity of SA_5th, SA_7th and EO for dyskinesis group during execution of push-up on unstable surface. In both groups positive correlations (r > 0.47) were observed between EMG activity of SA and EO. In the exercises tested, there seems to be an anatomical and functional relationship between the SA and EO muscles. The use of the unstable surface promotes increased neuromuscular demand, but the neuromuscular strategies appear to differ between groups.  相似文献   

17.
18.
This paper provides a critique of the article by Gary James and Dave Day on ‘The Emergence of an Association Football Culture in Manchester, 1840–1884', published in Sport in History. We suggest an alternative interpretation of Manchester's football history during this period, arguing that Association football was a minor form of football in a city largely dominated by the rugby code. Furthermore, by employing an artificial construct of Manchester the authors have produced the wrong answer to the wrong question. Rather than trying to prove that Manchester developed an important Association football culture, we suggest they ought to have addressed the question of why such a culture did not exist. The contribution to the development of Association football of three isolated ‘transitory’ clubs in a city as large as Manchester is certainly not ‘substantial’. Subsequently, James and Day also fail to exploit fully their evidence for early football in the Manchester area by omitting to relate this properly to the much wider ongoing debate surrounding the origins of football. Conversely, there is ample evidence that ‘substantial’ Association football developments actually occurred in East Lancashire, centred on Bolton, Blackburn and Darwen, developments that are scarcely noted in James and Day's account.  相似文献   

19.
This paper examines the manner in which the Japanese colonial government influenced the development of baseball in Taiwan during the period from 1895 to 1945. The paper seeks to explain the role that baseball played in the divided society of this period. It argues that baseball was a political vehicle used by the Japanese colonial government to promote social integration and it evaluates the responses of the Taiwanese to baseball utilized for this purpose.  相似文献   

20.
The purpose of this study was to analyse the response to Tony Stewart’s first public statement following the Kevin Ward Jr. incident and determine how individuals were discussing the incident on Facebook utilizing the theoretical lens of framing. A total of 14,888 comments from 4594 users were analysed with the qualitative software Leximancer. Two frames emerged from the data analysis including judgement and knowledge. Within those frames were five themes including fault, accident, conviction, racing knowledge and evidence. These themes were bi-directional in nature, which allowed users to place blame, question other users’ knowledge, analyse the nature of the incident itself, express support or disdain and call for further examination of the incident. This study’s findings highlight how Facebook can be utilized as a platform for individuals to create an organic framework and attribute their own meaning to a controversial incident.  相似文献   

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