We investigated the effects of aerobic exercise intensity on oxidative–nitrosative stress, neurotrophic factor expression, and blood–brain barrier (BBB) permeability. Fifteen healthy men performed treadmill running under low-intensity (LI), moderate-intensity (MI), and high-intensity (HI) conditions. Blood samples were collected immediately before exercise (IBE), immediately after exercise (IAE), and 60 min after exercise (60MAE) to examine oxidative–nitrosative stress (reactive oxygen species [ROS]; nitric oxide [NO]), neurotrophic factors (brain-derived neurotrophic factor [BDNF]; nerve growth factor [NGF]), and blood-brain barrier (BBB) permeability (S-100β; neuron-specific enolase). ROS concentration significantly increased IAE and following HI (4.9 ± 1.7 mM) compared with that after LI (2.8 ± 1.4 mM) exercise (p < .05). At 60MAE, ROS concentration was higher following HI (2.5 ± 1.2 mM) than after LI (1.5 ± 0.5 mM) and MI (1.4 ± 0.3 mM) conditions (p < .05). Plasma NO IAE increased significantly after MI and HI exercise (p < .05). Serum BDNF, NGF, and S-100b levels were significantly higher IAE following MI and HI exercise (p < .05). BDNF and S-100b were higher IAE following MI (29.6 ± 3.4 ng/mL and 87.1 ± 22.8 ng/L, respectively) and HI (31.4 ± 3.8 ng/mL and 100.6 ± 21.2 ng/L, respectively) than following LI (26.5 ± 3.0 ng/mL and 64.8 ± 19.2 ng/L, respectively) exercise (p < .05). 60MAE, S-100b was higher following HI (71.1 ± 14.5 ng/L) than LI (56.2 ± 14.7 ng/L) exercise (p < .05). NSE levels were not significantly different among all intensity conditions and time points (p > .05). Moderate- and/or high-intensity exercise may induce higher oxidative-nitrosative stress than may low-intensity exercise, which can increase peripheral neurotrophic factor levels by increasing BBB permeability.
Hee-Tae Roh, Su-Youn Cho, Hyung-Gi Yoon and Wi-Young So
Tina Louisa Cook, Ilse De Bourdeaudhuij, Lea Maes, Leen Haerens, Evangelia Grammatikaki, Kurt Widhalm, Lydia Kwak, Maria Plada, Luis Alberto Moreno, Yannis Tountas, Antonis Zampelas, Yannis Manios and on hehalf of the HELENA group
The aim was to examine if psychosocial determinants (attitudes, self-efficacy, social support from a sports partner) and perceived environmental barriers (PEB) of physical activity (PA) mediated the effect of a 3-month Internet-based intervention on PA in European adolescents.
A sample of 536 adolescents (51% boys) aged 12–17 years were randomly assigned to intervention or control condition. Questionnaires were used to assess different PA behaviors, psychosocial determinants and PEB at baseline and at 3-month follow-up. Mediating effects were assessed with the bootstrapping method.
PEB regarding neighborhood safety mediated the effect of the intervention on all PA indices. PEB regarding sports facilities availability at neighborhood and PEB regarding sport-related facilities availability at school mediated the effect of the intervention on moderate to vigorous PA (MVPA) and moderate PA (in leisure time and at school, respectively). Social support from a sports partner suppressed the effect of the intervention on vigorous PA and MVPA. No other factor had a mediation effect.
All PEB measures appear to mediate PA behaviors of different intensities and in different contexts. Interventions promoting PA in adolescents should also focus on improving the targeted PEB as mediators of engagement in PA to bring the desired effects in actual behaviors.
Paul Rainer, Robert Griffiths, Brendan Cropley and Stuart Jarvis
In light of recent reports, schools must be realistic in that physical activity recommendations cannot be met through curriculum PE alone. However, extracurricular PE and school sport has the potential to further promote physical activity in adolescents. Consequently, the Welsh Government, UK, proposed through its Climbing Higher strategy (2006) for secondary school children to achieve 60 minutes of physical activity a day. This was implemented through Sport Wales and the 5×60 scheme.
This study aimed to examine the experiences of the 5×60 officers responsible for implementing the program, with a view to gain an understanding of the barriers associated with increasing participation in physical activity. Officers from 14 unitary authorities across Wales were interviewed using a socioecological approach that considered the impact of: personal behaviors, physical environment, social environment, and policy.
Participants reported a number of challenges affecting the delivery of the program, including: availability of facilities, lack of support from senior management, time, and conflict with PE staff.
This study suggests that current methods used by personnel to facilitate extracurricular school sport may not be the most appropriate, and future direction should consider the place and contribution of physical activity to young people’s lives.
Diane E. Whaley and Vicki Ebbeck
This study used a qualitative, feminist perspective to examine issues pertaining to exercise constraints among older adults. Participants were 8 male and 9 female older adults (mean age = 76.7) who chose not to engage in structured exercise classes. Twenty-six self-identified constraints were elicited (mean = four per person). Additionally, four constraints per person from previous research were selected. The most frequently cited self-reported constraints were “get enough exercise elsewhere,” health-related items, and issues related to time. From the constraints most frequently cited in past studies, inconvenience, time, and type of activity were selected most often. Gender differences were apparent in the constraints chosen as well as reasons why a particular constraint inhibited or prohibited activity. Specific suggestions for strategies included having programs with a purpose, building in flexibility, and encouraging men to participate. The influence of gender is explored, especially how expanding our understanding of gender issues might improve program planning.
Jonathan M. Casper, Jason N. Bocarro, Michael A. Kanters and Myron F. Floyd
Organized sport is viewed as a viable medium for promoting more physical activity among youth. However, participation in youth sport declines significantly among both boys and girls during their middle school years. This study examined middle school students’ perceived constraints to sport participation.
Middle school students from 4 schools (6th−8th grade, N = 2465) completed a web based survey (97.3% response rate). Descriptive analysis, t tests, and ANOVA were used to assess extent of perceived constraints and differences among demographic and sport participation level subgroups.
The most salient constraint perceived by respondents was time, while knowledge was perceived as the lowest among the overall sample. Significant (P < .01) differences in perceived constraints were found among all comparisons groups. Girls, Latinos, lower SES students, and students who did not play sports reported more constraints than respective comparisons groups.
The sociodemographic characteristics of middle school students appear to be a significant factor in their perception of constraints to sport participation. Identifying constraints associated with sport participation can enable policy-makers and administrators to be more deliberate in channeling resources.
Mitch J. Duncan, Hannah M. Badland and William Kerry Mummery
The aim of this study was to examine the relationship between occupational category and 3 health-related behaviors: participation in leisure-time physical activity, active transport (AT) and occupational sitting in a sample of employed Australian adults.
A random, cross-sectional sample of 592 adults aged 18 to 71 years completed a telephone survey in October/November 2006. Reported occupations were categorized as professional (n = 332, 56.1%), white-collar (n = 181, 30.6%), and blue-collar (n = 79, 13.3%). Relationships between occupational category and AT, sufficient physical activity and occupational sitting were examined using logistic regression.
White-collar employees (OR = 0.36, 95% CI 0.14−0.95) were less likely to engage in AT and more likely to engage in occupational sitting (OR = 3.10, 95% CI 1.63−5.92) when compared with blue-collar workers. Professionals (OR = 3.04, 95% CI 1.94−4.76) were also more likely to engage in occupational sitting compared with blue-collar workers. No relationship was observed between occupational category and engagement in sufficient physical activity.
No association between occupational category and sufficient physical activity levels was observed, although white-collar and professionals were likely to engage in high levels of occupational sitting. Innovative and sustainable strategies are required to reduce occupational sitting to improve health.
Pamela A. Bechtel and Mary O’Sullivan
The purpose of this study was to explore enhancers and inhibitors that impacted 4 secondary physical education teachers to make changes in their programs. An interpretivist approach was used to understand the physical educators’ change process. Data were collected from document analyses, participant information sheets, interviews, discussion groups, and observing classes. Data were analyzed as 4 case studies using inductive analysis that examined emergent themes for each participant. A cross-case analysis highlighted the common enhancers and inhibitors for the teachers’ change process. The enhancers to change were the teachers’ visions and beliefs of physical education and support from principals, colleagues, and students. The inhibitors to change were district practices and policies and educational priorities. Gaining a better understanding of the teacher change process will help to design more effective professional development programs for secondary physical education teachers.
Keith R. Johnston, Donna L. Goodwin and Jennifer Leo
Dignity, as an essential quality of being human, has been overlooked in exercise contexts. The aim of this interpretative phenomenological study was to understand the meaning of dignity and its importance to exercise participation. The experiences of 21 adults (11 women and 10 men) from 19 to 65 yr of age who experience disability, who attended a specialized community exercise facility, were gathered using the methods of focus-group and one-on-one interviews, visual images, and field notes. The thematic analysis revealed 4 themes: the comfort of feeling welcome, perceptions of otherness, negotiating public spaces, and lost autonomy. Dignity was subjectively understood and nurtured through the respect of others. Indignities occurred when enacted social and cultural norms brought dignity to consciousness through humiliation or removal of autonomy. The specialized exercise environment promoted self-worth and positive self-beliefs through shared life experiences and a norm of respect.
Nicholas M. Edwards, Gregory D. Myer, Heidi J. Kalkwarf, Jessica G. Woo, Philip R. Khoury, Timothy E. Hewett and Stephen R. Daniels
Evaluate effects of local weather conditions on physical activity in early childhood.
Longitudinal prospective cohort study of 372 children, 3 years old at enrollment, drawn from a major US metropolitan community. Accelerometer-measured (RT3) physical activity was collected every 4 months over 5 years and matched with daily weather measures: day length, heating/cooling degrees (degrees mean temperature < 65°F or ≥ 65°F, respectively), wind, and precipitation. Mixed regression analyses, adjusted for repeated measures, were used to test the relationship between weather and physical activity.
Precipitation and wind speed were negatively associated with total physical activity and moderate-vigorous physical activity (P < .0001). Heating and cooling degrees were negatively associated with total physical activity and moderate-vigorous physical activity and positively associated with inactivity (all P < .0001), independent of age, sex, race, BMI, day length, wind, and precipitation. For every 10 additional heating degrees there was a 5-minute daily reduction in moderatevigorous physical activity. For every additional 10 cooling degrees there was a 17-minute reduction in moderate-to-vigorous physical activity.
Inclement weather (higher/lower temperature, greater wind speed, more rain/snow) is associated with less physical activity in young children. These deleterious effects should be considered when planning physical activity research, interventions, and policies.
Lesley Day, Margaret J. Trotter, Alex Donaldson, Keith D. Hill and Caroline F. Finch
The study aim was to evaluate the implementation of group- and home-based exercise falls prevention programs delivered through community health agencies to community-dwelling older people. Interviews with program staff were guided by the Diffusion of Innovations theory. Highly consistent themes emerged for the two types of programs. Both had high overall compatibility, high relative advantage, good observability and high inherent trialability—all factors known to strengthen implementation. The level of complexity and low financial compatibility emerged as the strongest potential inhibitors to program implementation in the context examined. The two main factors contributing to complexity were the need to challenge balance safely across a broad range of capability, and practical considerations associated with program delivery.A range of strategies to provide more technical support for exercise program leaders to tailor balance challenge for exercise program leaders may enhance implementation of falls prevention exercise programs.