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61.
Longitudinal associations among different types of organized activity involvement, problem peer associations, and cigarette smoking were examined in a sample of 1040 adolescents (mean age = 15.62 at baseline, 16.89 at 15-month assessment, 17.59 at 24 months) enriched for smoking experimentation (83% had tried smoking). A structural equation model tested longitudinal paths between three categories of involvement (team sports, school clubs and activities, and religious activities, measured at baseline and 15 months), problem peer associations (baseline and 15 months), and cigarette smoking behavior (baseline and 24 months). Multi-group analyses indicated pathways differed by type of activity and adolescent gender. Boys' baseline team sports and religious involvement predicted lower levels of smoking at 24 months via continued activity involvement at 15 months. Girls' involvement in school clubs and activities and religious activities indirectly predicted lower levels of smoking at 24 months via reduced exposure to problem peers at 15 months.  相似文献   
62.
ObjectivesThe present study was to examine the relationship between exercise type and inhibitory function in older adults using neuroelectric indices.DesignA cross-sectional design was employed in the present study.MethodSixty adults (M = 69.42 years) were categorized into open-skill, closed-skill, and irregular exercise groups according to their history of exercise participation. The participants conducted a flanker task while their behavioral performance and event-related brain potentials were assessed.ResultsThe results indicated that regular exercisers, regardless of exercise type, exhibited a faster reaction time across conditions of the flanker task compared to irregular exercisers. For the P300 amplitude of the open-skill exerciser group, the peak amplitude was larger at the vertex site compared to the frontal site, whereas no site differences were observed in the closed-skill and irregular exerciser groups.ConclusionsThese findings extend current knowledge by suggesting that, for older adults, participation in physical exercise involving increased cognitive demand is associated with better neural efficiency in resource allocation for tasks that require interference control.  相似文献   
63.
ObjectivesThis review examined the potential impact of sport and physical activity upon the subjective and psychological well-being of combat veterans in the aftermath of physical or psychological combat trauma.DesignA systematic review was conducted. The question guiding this review was ‘what is the impact of sport and physical activity on the well-being of combat veterans?’MethodsKey databases were searched for articles relating to the use of sport and/or physical activity in supporting combat veterans. 11 studies were identified as relevant for inclusion. Data from these studies were extracted by means of a directed content analysis, the results of which were reported in a narrative synthesis.ResultsSport and physical activity enhances subjective well-being in veterans through active coping and doing things again, PTSD symptom reduction, positive affective experience, activity in nature/ecotherapy, and quality of life. Impact on psychological well-being includes determination and inner strength, focus on ability and broadening of horizons, identity and self-concept, activity in nature/ecotherapy, sense of achievement/accomplishment, and social well-being. Participating in sport and/or physical activity can also enhance motivation for living.ConclusionsThe review advances knowledge by producing a synthesis of evidence that highlights the value of sport and physical activity for supporting the well-being and rehabilitation of disabled combat veterans and combat veterans diagnosed with Post-Traumatic Stress Disorder. It also develops knowledge by identifying the type of sports and physical activities used to promote well-being, offering the first definition of combat veterans in the sport literature, taking a critical approach, and highlighting the under researched role of nature-based physical activity.  相似文献   
64.
ObjectiveThe primary aim of the present study was to investigate whether construing action abstractly versus concretely increases physical activity over a one-week period.Design and methodAn experimental study was conducted in which participants were asked to commit to engaging in physical activity at least four times in the coming week. After making this commitment, participants were assigned randomly to think about the concrete procedures or the abstract purpose of their actions. Additionally, in an attempt to induce differences in level of goal conflict, participants were assigned randomly to receive a reminder of a different or consistent goal. The main outcome variable of interest was the number of minutes spent on physical activity over the following 7-day period.ResultsConsistent with the hypothesis, participants in the abstract condition reported engaging in significantly more minutes of physical activity than did those in the concrete condition. Level of goal conflict did not significantly impact physical activity. The effect of abstract versus concrete thinking on physical activity also was related to the processing of negative affect.ConclusionBy providing evidence that construing action abstractly impacts physical activity, the present investigation makes an important addition to research aiming to identify effective means of increasing physical activity.  相似文献   
65.
Physical activity (PA) plays an essential part in the secondary prevention of persons with coronary heart disease (CHD). A substantial amount of PA can be gained through increasing the use of active transport modes (walking or cycling for at least 10 min/day) in CHD patients’ daily routine, benefiting the mortality and morbidity rate as well as the environment. The current study aims to investigate the utility of the Theory of Planned Behaviour (TPB) framework extended with habit strength, in understanding the behavioural intention and the behaviour of using active transport modes during the daily travel routine of CHD patients. A cross-sectional survey was conducted from 131 CHD patients. The behaviour was measured using three self-report methods; 1) scale measure, the walking or cycling frequency, 2) direct ATS (Active Travel Score, PA calculated by the directly reported aggregated time spent per day for walking or cycling for travel purposes), and 3) indirect ATS (PA calculated by combining the duration spent on trips by walking and cycling from the self-reported one-day travel diary). Additionally, the participants completed surveys on the direct measures of TPB constructs and habit strength. The results indicated that the TPB constructs explained a 38% variance in the intention to use active transport modes of CHD patients, by which the variance increased to 59% with the addition of habit strength. On the contrary, different behavioural measures were explained differently by TPB and habit strength. The scale measure of behaviour was best predicted (up to 21%) by TPB and habit strength. However, the direct and indirect measures of behaviour were poorly explained (up to 3% and 10% only, respectively). Habit strength moderated the relationship between behaviour (scale measure) and behavioural intention. Surprisingly, higher behavioural intention resulted in a lower behavioural frequency when the habit strength to be active is low. This suggests a limited control over the behaviour thus indicating the intention-behaviour gap. The current study findings highlight the inconsistent predictive utility of TPB across different types of behavioural self-report measures, targeted at the use of active transport modes in CHD patients. However, considering this study as hypothesis-generating, further research is necessary to replicate and extend these findings.  相似文献   
66.
Understanding the malleable factors that underpin people’s ongoing commitment to specific forms of exercise is crucial to facilitate more effective efforts to improve participation rates. To this end, we examined the role of (a) perceiving the members of one’s exercise class to be similar to each other on various dimensions, and (b) possessing a strong social identity as an exercise class member in shaping one’s future participation in that class. During a 3-week intensive sampling period, 779 unique responses were obtained from 278 attendees (who were invited to complete a questionnaire on each occasion they attended an exercise class). On each questionnaire, participants indicated their perceptions of class members’ similarity and their own social identification in relation to the exercise class they had just participated in. Participation was conceptualised as attendance at the same class (i.e., same time and type) the following week and was measured objectively using the fitness facility’s electronic class attendance records. Linear multilevel models showed that participants identified more strongly as members of exercise classes in which they perceived that their fellow attendees were similar to each other: both in general, and in terms of age, physical fitness, and their attitude towards the class. Participants also tended to be more likely to attend a given exercise class the following week to the extent that they reported a strong sense of social identification as a member of that class. These relationships were replicated in a multilevel mediation model, which revealed a significant indirect effect of similarity on class attendance through social identification. Results point to the role that social identification can play in promoting repeated exercise participation and indicate that one way to facilitate exercisers’ greater social identification might be to purposefully create exercise classes and groups comprised of relatively homogenous individuals.  相似文献   
67.
Grounded in social cognitive theory (SCT), this study sought to examine whether parents perceived social cognitive factors regarding children's physical activity (PA) behaviors were associated with preschool children's moderate-to-vigorous PA (MVPA) levels. A total of 142 Hong Kong parent-child pairs from five preschools/childcare centers completed all assessments in the cross-sectional study. Children’s (42% girls; mean age = 4.52 ± 0.67 years) PA was measured through accelerometers. Parents (74% mothers; mean age = 37.38 ± 4.63 years) completed a paper-based questionnaire assessing the social cognitive factors on their children’s PA participation. The data were analyzed using latent variable structural equation modeling. Findings revealed that the model showed acceptable fit with the data: χ2 (23) = 38.14, p = .025, χ2/df = 1.66, CFI = 0.955, TLI = 0.929, RMSEA = 0.068, 90% CI [0.025, 0.106], and SRMR = 0.072. The model accounted for 39.1% of the variance in the PA behavior of preschool-aged children. Structural equation modelling revealed parental self-efficacy (β = 0.29, 95% CI [0.95, 0.49]) and goal setting (β = 0.25, 95% CI [0.06, 0.44]) were directly associated with children’s MVPA. Outcome expectations (β = 0.09, 95% CI [0.01, 0.03]) and goal setting (β = 0.18, 95% CI [0.05, 0.32]) mediated the association between parental self-efficacy and children’s MVPA. Indirect associations of parental self-efficacy from setting goals via parental support (β = 0.15, 95%CI [0.02, 0.30]) and perceived barriers (β = 0.15, 95% CI [0.05, 0.28]) were uncovered. Results supported the use of SCT in understanding how the parents perceived social cognitive factors predict the PA behaviors of young children. This study provides insight into whether these theoretical variables could be modified or promoted in future intervention programs. Enhancing parents’ abilities to ensure preschool-aged children are physically active is of great importance given the global decline in PA among children.  相似文献   
68.
Bulimia nervosa (BN) is characterized by a pattern of binge eating and compensatory behaviors as well as an overemphasis on body weight and shape in self-evaluation. Although cognitive behavioral therapy (CBT) is efficacious, recent reviews suggest that only 30% of patients reach abstinence at posttreatment. One potential reason for these poor outcomes is that CBT fails to adequately reduce elevated negative affect (NA) and shape and weight concern, which have been shown to be correlated with poorer treatment outcomes in BN. Therefore, novel treatment components that focus on improving NA and shape and weight concern are needed in order to enhance outcomes. Promoting physical activity (PA) is a promising avenue through which to reduce NA and improve body image in healthy individuals, other clinical populations (e.g., individuals with depression or anxiety), and individuals with eating disorders. While prescribing PA for individuals with BN has been controversial (due to concerns that exercise maybe be used to compensate for binge episodes or become driven or compulsive), this approach may have many benefits, including promoting healthy lifetime exercise habits that reduce likelihood of relapse through the improvement of emotion regulation skills and weight regulation.Given the promise of PA for targeting key maintenance factors of BN, we developed a 12-session healthy PA promotion intervention for BN and tested initial feasibility, acceptability, and preliminary target engagement in an iterative case series design (n = 3). The treatment provided cognitive-behavioral skills designed to identify, practice, and achieve behavioral goals while asking patients to engage in up to 150 minutes of moderate-to-vigorous PA per week, which was preplanned during each session with the client’s therapist.Results suggested that the healthy PA promotion intervention was both feasible and acceptable to deliver. In addition, the intervention resulted in a clinically significant decrease in BN symptom frequency in each participant. Further, participants showed clinically significant decreases in NA and shape and weight concern.The current study demonstrates that healthy PA interventions can have beneficial effects on BN symptoms, NA, and shape and weight concern. However, due to the small sample size, conclusions must be treated with caution. Future research should investigate additional approaches for promoting healthy PA and include a larger sample in order to further test initial efficacy of this treatment approach.  相似文献   
69.
This driving simulator study, conducted as a part of Horizon2020-funded L3Pilot project, investigated how different car-following situations affected driver workload, within the context of vehicle automation. Electrocardiogram (ECG) and electrodermal activity (EDA)-based physiological metrics were used as objective indicators of workload, along with self-reported workload ratings. A total of 32 drivers were divided into two equal groups, based on whether they engaged in a non-driving related task (NDRT) during automation (SAE Level 3) or monitored the drive (SAE Level 2). Drivers in both groups were exposed to two counterbalanced experimental drives, lasting ∼ 18 min each, of Short (0.5 s) and Long (1.5 s) Time Headway conditions during automated car-following (ACF), which was followed by a takeover that happened with or without a lead vehicle. Results showed that driver workload due to the NDRT was significantly higher than both monitoring the drive during ACF and manual car-following (MCF). Furthermore, the results indicated that a lead vehicle maintain a shorter THW can significantly increase driver workload during takeover scenarios, potentially affecting driver safety. This warrants further research into understanding safe time headway thresholds to be maintained by automated vehicles, without placing additional cognitive or attentional demands on the driver. Our results indicated that ECG and EDA signals are sensitive to variations in workload, which warrants further investigation on the value of combining these two signals to assess driver workload in real-time, to help future driver monitoring systems respond appropriately to the limitations of the driver, and predict their performance in the driving task, if and when they have to resume manual control of the vehicle after a period of automated driving.  相似文献   
70.
From a sport and exercise psychology perspective, both the actual and perceived physical fitness become important for motivation towards physical activity and persistent physical activity in children no later than middle childhood (Stodden et al., 2008). To date, the effects of actual and perceived physical fitness have been investigated from a variable-centered approach (Jekauc et al., 2017). However, within this approach, the accuracy of the perceived physical fitness remains unconsidered. As actual and perceived physical fitness levels can be divergent, especially in children due to greater egocentricity and hence less comparison processes (Harter, 2006), also the accuracy of perceived physical fitness should be considered.In total, 462 children from 3rd and, approximately nine months later, from 4th grade participated in this study (Mage = 8.79 years). Third-grade students were assessed on their actual physical fitness, perceived physical fitness, and physical activity. In fourth grade, students were asked to fill out questionnaires that assess motivational regulations and physical activity. Polynomial regressions with response surface analyses were conducted to analyze main effects and accuracy effects of actual and perceived physical fitness on motivation and physical activity. Analyses revealed that children with higher actual and perceived physical fitness levels show greater autonomous motivation, higher current physical activity levels and higher physical activity levels nine months later. In addition, children who perceive their physical fitness more accurately show more current physical activity. Results indicate that the interplay between actual and perceived physical fitness does not only have an effect on physical activity but also on autonomous motivation, which is a predictor for long-term physical activity. Therefore, intervention should focus on the promotion of actual and perceived physical fitness. In addition, the ability to accurately assess fitness should be promoted in this age group.  相似文献   
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