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After school physical activity intervention: Changes and challenges over a three-year-period
Thursday 1 November Papers / Journal of Science and Medicine in Sport 15 (2013) S34–S126
281 Physically active at school–It’s child’s play. The Sydney Playground Project L. Engelen 1,∗ , G. Naughton 2 , A. Bundy 1 , S. Wyver 3 , A. Bauman 4 , L. Baur 5 , G. Perry 1 , G. Jessup 1 , J. Ragen 1 1
Faculty of Health Sciences, University of Sydney Centre of Physical Activity Across the Lifespan, Australian Catholic University 3 Institute of Early Childhood, Macquarie University 4 Public Health, University of Sydney 5 Paediatrics and Child Health, University of Sydney 2
Introduction: This research was part of a larger study known as the Sydney Playground Project (SPP), which aims to increase physical activity and social skills in primary school children by means of a low-cost innovative playground intervention. For many children pure sports interventions are not the answer, hence this study engaged children’s playful nature to promote physical activity and social interactions through play. The purpose of this part of the study was to study the effect of the intervention on physical activity. Methods: 214 (115 boys, 99 girls) 5–7 year old (mean: 6.0 years at baseline) children from 12 Sydney primary schools participated in this CRCT. Baseline data were collected prior to a 14-week playground intervention or recess as normal, followed by post-testing during the last week of intervention. The playground intervention: unstructured items, consisting of or made from recycled material (tyres, balance beams, crash mats) introduced to the school playgrounds for the children to play with freely. Physical activity was measured by accelerometers during school days (0900–1500 for 5 consecutive days at baseline and post-test. Height, weight and BMI were measured. Mixed-effect ML regression (STATA/IC 12), taking clustering and repeated measures into account were used to examine net change from baseline values between groups. Results: Over time, MVPA increased (1.82 min, p = 0.006), and sedentary time decreased (-2.13 min, p = 0.01) significantly during recess in the intervention group, however effect sizes were small. Activity increased independent of BMI. Anecdotally, schools and children were enthusiastic about the playground intervention, quoting less playground demeanour and more fun. Discussion: This play intervention has the potential to be a costeffective way to engage children in increased physical activity and social interactions and can potentially be implemented in a large range of settings. http://dx.doi.org/10.1016/j.jsams.2012.11.284 282 Uptake and effects of a new sport program at a school in a disadvantaged locality A. Hahn 1,3,4,∗ , P. Terry 1,2 , M. Simjanovic 1 1
Queensland Academy of Sport Univeristy of Southern Queensland 3 University of Canberra 4 Victoria University 2
Introduction: On any day, ∼55% of 11–13-year-olds play some kind of sport. However, recent research has shown that there are demographic effects on the activity patterns of children, with youth from lower socio-economic and single-parent family structures less likely to participate. This study investigated the uptake by 11–12 year olds in a disadvantaged locality of a new
S117
sport involving a modified, low-risk form of boxing (Box’Tag), and assessed the outcomes of their involvement. Methods: All grade 7 students (N = 146) from an urban Queensland primary school were invited to participate in an 8-week, lunchtime sport program consisting of 3 sessions per week. Prior to commencement of the study, senior teaching staff dichotomized all children as either “at risk” or “not at risk” of social disengagement based on each child’s observed behaviour. In July 2011, 35% of children (51/146) volunteered to participate. A total of 47 of the 51 volunteers (92%) completed the program and on average attended 70% of the sessions. No injuries resulting from participation occurred. The Brunel Mood Scale (BRUMS) and the Strengths and Difficulties Questionnaire (SDQ) were administered at baseline (T1), 4 weeks (T2), 8 weeks (T3) and 12 weeks (T4). Participants completed a shuttle run test at T1 and T3. Results: In contrast to previous research in which participation in voluntary sport programs was typically higher among boys, the proportion of males and females nominating for this study was not significantly different to that of the entire grade (2 = 0.75, p = .39). Whereas 27% (40/146) of grade 7 children were identified as “at risk” of social disengagement, 43% of the volunteers for the program (22/51) were in this category, which was significantly more than expected (2 = 68.0, p < .001). The Box’Tag group showed greater improvement in shuttle run performance than controls (F = 4.64, p = .038, d = .69). No significant differences were found for BRUMS or SDQ scores, although the Box’Tag group reported more positive trends than controls for total mood disturbance from T1 to T2. Subjective reports from teachers indicated that several students showed substantial improvements in general behaviour. Discussion: The findings suggest that this new sport program appeals to school age children of both sexes, specifically engages children at risk of social disengagement, may have positive effects on aerobic fitness and mood, and for some students may yield overall behavioural benefits. http://dx.doi.org/10.1016/j.jsams.2012.11.285 283 After school physical activity intervention: Changes and challenges over a three-year-period A. Pienaar ∗ School of Biokinetics, Recreation and Sport Science, North West University, Potchefstroom Campus Background: Researchers report declining trends in PA among adolescents. Those living in low SES environments are also hampered by additional constraints to be active. This study aimed to determine the PA levels and patterns of adolescents after participating in an after school physical activity (PA) intervention study over a 3-yr period. Methods: 309 black adolescents (158 boys, 211 girls) from a disadvantaged environment in South Africa, (M = 14.9 ± 1.4 years boys; 14.3 ± 1.4 years girls) participated in the study. An intervention group participated in an after school health related PA intervention (N = 282) for two years, without any PA intervention in the 3rd year of the study, and was then compared to a control group (N = 87) who received no PA intervention. Final measurements were taken at the end of the 3rd year of the study when no PA intervention took place. Multi-level modelling (repeated measures analysis of co-variance (ANCOVA) and repeated measures analysis of variance (ANOVA) over time, with a Bonferroni post hoc test were used to analyse the data. Week and weekend PA levels and patterns were analysed separately.
S118
Thursday 1 November Papers / Journal of Science and Medicine in Sport 15 (2013) S34–S126
Results: The results showed similar mean PA levels among the two groups of boys (p > 0.05) during baseline, with a significantly higher mean level of PA after 3 years in the intervention group (p < 0.05). Baseline measurements for girls indicated statistically significant mean differences during the week and the weekend, although these differences were not significant during the final measurements three years later. Boys and girls (excluding the intervention group of boys), showed a tendency of declining mean PA over the 3 year period. The PA intervention showed a stabilising effect on the mean PA levels and contributed to more active choices among the intervention group of boys, especially over weekends. Conclusions: Participation in similar PA interventions is recommended for adolescent boys, with adaptations to the content of such PA programs for girls. Such interventions should however be part of the school day, because adolescents living in disadvantaged environments have among other various barriers after school to overcome to be active, which should be addressed by health practitioners to improve the health benefits of such programs.
22%) than in the control group (boys 21%, girls 40%, combined 31%), with p = 0.03 for the combined data. Intervention teachers included more specific fitness work than control classes, mainly in the form of muscular strength and endurance (7 min v 1 min, p < 0.001) associated with dynamic and static postural challenges. Intervention classes also involved more moderate and vigorous physical activity (17 min v 10 min, p < 0.001), but there was no evidence of any four-year intervention effect on daily steps, CRF or %BF. Discussion: By the age of 12, IR had increased to levels of concern in more than a quarter of these apparently healthy children, but well-designed PE attenuated the increase. Given that attention to risk factors during childhood and adolescence is likely to reduce the risk of chronic disease in adults, our data show that primary school PE can play an important role in early preventative medicine.
http://dx.doi.org/10.1016/j.jsams.2012.11.286
Short-interval intracortical inhibition is not affected by varying the complexity of an isometric task in biceps brachii muscle
284 Can physical education improve insulin resistance in healthy boys and girls? The LOOK study Telford 1,∗ ,
Cunningham 2 ,
Daly 3 ,
Telford 4 ,
Olive 5 ,
R. R. R. R. L. A. Lafferty 6 , J. Potter 7 , P. Hickman 7 , E. Southcott 7 , W. Abhayaratna 1 1
Clinical Trials Unit Canberra Hospital and Medical School, Australian National University 2 Fenner School of Environment and Society, Australian National University 3 Centre for Physical Activity and Nutrition Research, Deakin University 4 Centre for Research and Action in Public Health, University of Canberra 5 Department of Psychology, Australian National University 6 Paediatrics and Child Health, Canberra Hospital and Medical School, Australian National University 7 ACT Pathology and Medical School, Australian National University Introduction: With low physical activity (PA) and cardiorespiratory fitness (CRF) in childhood being risk factors for insulin resistance (IR) and type 2 diabetes in adulthood, physical education (PE) in schools provides an ideal opportunity to introduce an early preventative strategy. However there is no evidence to date that primary (elementary) school-based PE can improve IR. Methods: Participants in this 4-year cluster-randomized intervention study were 229 boys and 239 girls in grade 2, initially 8.1 (SD 0.31) years, from 29 primary schools. The curriculum prescribed 150 min/week PE from general classroom teachers, but in 13 schools 100 min/week was replaced with two classes of an intervention program conducted by specialist PE teachers from the not for profit Bluearth Foundation. The remaining schools formed the control. The System of Fitness Instruction Time (SOFIT) was used to compare class activities. Measurements in grades 2, 4 and 6 included fasting blood glucose and insulin for calculation of the homeostatic model of insulin resistance (HOMA-IR), percent body fat (%BF, DXA), PA (7 day pedometers and accelerometers), CRF (multistage run) and pubertal development (Tanner stage selfassessment) and socioeconomic status. Results: With no group differences at baseline, by grade 6 the intervention had lowered IR by 14% (95% CI 1–31) in the boys and 9% (5–26) in the girls. Also by grade 6, the percentage of children with IR greater than 3, a published cut-off point for paediatric metabolic risk, was lower in the intervention (boys 12%, girls 32% combined
http://dx.doi.org/10.1016/j.jsams.2012.11.287 285
D. Kidgell ∗ , M. Leung, C. Brandner, M. Spittle, A. Weier, T. Rantalanen Deakin University Introduction: There is considerable evidence that the excitability of neural networks involved in motor control is modulated in a task-dependant manner. At the level of the primary motor cortex (M1), corticomotoneurons have been shown to be more active during complex tasks. These changes in neural excitability are an adaptive response to the requirements of the motor task. However, the effect of varying the difficulty or complexity of the same task on the excitability of neural circuits is less understood, despite the importance of task-complexity in the rehabilitation of fine motor skill. The purpose of this study was to determine whether taskdependant differences in motor cortical network excitability occur when varying the complexity, via visuomotor feedback of an elbow flexion task. Methods: Focal transcranial magnetic stimulation (TMS) was used to measure corticospinal excitability and short-intervalintracortical inhibition (SICI) of the contralateral biceps brachii (BB) in 10 healthy subjects, performing two isometric tasks of differing visuomotor demand at 5, 20 & 40% of maximum voluntary contraction force (MVC). To produce two tasks with differing visuomotor demand, the scaling of the on-line torque trace was modified. Results: Corticospinal excitability did not differ between tasks (p > 0.05), did differ between torque levels (p < 0.05) and there was no task x torque level interaction effect (p > 0.05). SICI did not differ between tasks (p > 0.05), did between torque levels (p < 0.05) and there was no task x torque level interaction (p > 0.05). Discussion: This study shows that the excitability of intracortical neural networks namely, intracortical inhibition; is reduced during increasing levels of torque production. The present findings demonstrate the influence of target torque levels on disinhibition of corticospinal neurons (i.e. increase M1 excitability), modulated by neurons responsible for SICI. Conclusion: This study has demonstrated that intracortical inhibition is reduced during graded voluntary muscle action, which suggests that force production is modulated by neurons confined to the M1. Interestingly, the level of inhibition is not altered when varying the difficulty of the same task. This finding, which is in contrast to findings on lower arm musculature, suggests that SICI is more markedly modulated by force gradation than by task visuomotor demands at least in the BB muscle. These findings have
281 Physically active at school–It’s child’s play. The Sydney Playground Project L. Engelen 1,∗ , G. Naughton 2 , A. Bundy 1 , S. Wyver 3 , A. Bauman 4 , L. Baur 5 , G. Perry 1 , G. Jessup 1 , J. Ragen 1 1
Faculty of Health Sciences, University of Sydney Centre of Physical Activity Across the Lifespan, Australian Catholic University 3 Institute of Early Childhood, Macquarie University 4 Public Health, University of Sydney 5 Paediatrics and Child Health, University of Sydney 2
Introduction: This research was part of a larger study known as the Sydney Playground Project (SPP), which aims to increase physical activity and social skills in primary school children by means of a low-cost innovative playground intervention. For many children pure sports interventions are not the answer, hence this study engaged children’s playful nature to promote physical activity and social interactions through play. The purpose of this part of the study was to study the effect of the intervention on physical activity. Methods: 214 (115 boys, 99 girls) 5–7 year old (mean: 6.0 years at baseline) children from 12 Sydney primary schools participated in this CRCT. Baseline data were collected prior to a 14-week playground intervention or recess as normal, followed by post-testing during the last week of intervention. The playground intervention: unstructured items, consisting of or made from recycled material (tyres, balance beams, crash mats) introduced to the school playgrounds for the children to play with freely. Physical activity was measured by accelerometers during school days (0900–1500 for 5 consecutive days at baseline and post-test. Height, weight and BMI were measured. Mixed-effect ML regression (STATA/IC 12), taking clustering and repeated measures into account were used to examine net change from baseline values between groups. Results: Over time, MVPA increased (1.82 min, p = 0.006), and sedentary time decreased (-2.13 min, p = 0.01) significantly during recess in the intervention group, however effect sizes were small. Activity increased independent of BMI. Anecdotally, schools and children were enthusiastic about the playground intervention, quoting less playground demeanour and more fun. Discussion: This play intervention has the potential to be a costeffective way to engage children in increased physical activity and social interactions and can potentially be implemented in a large range of settings. http://dx.doi.org/10.1016/j.jsams.2012.11.284 282 Uptake and effects of a new sport program at a school in a disadvantaged locality A. Hahn 1,3,4,∗ , P. Terry 1,2 , M. Simjanovic 1 1
Queensland Academy of Sport Univeristy of Southern Queensland 3 University of Canberra 4 Victoria University 2
Introduction: On any day, ∼55% of 11–13-year-olds play some kind of sport. However, recent research has shown that there are demographic effects on the activity patterns of children, with youth from lower socio-economic and single-parent family structures less likely to participate. This study investigated the uptake by 11–12 year olds in a disadvantaged locality of a new
S117
sport involving a modified, low-risk form of boxing (Box’Tag), and assessed the outcomes of their involvement. Methods: All grade 7 students (N = 146) from an urban Queensland primary school were invited to participate in an 8-week, lunchtime sport program consisting of 3 sessions per week. Prior to commencement of the study, senior teaching staff dichotomized all children as either “at risk” or “not at risk” of social disengagement based on each child’s observed behaviour. In July 2011, 35% of children (51/146) volunteered to participate. A total of 47 of the 51 volunteers (92%) completed the program and on average attended 70% of the sessions. No injuries resulting from participation occurred. The Brunel Mood Scale (BRUMS) and the Strengths and Difficulties Questionnaire (SDQ) were administered at baseline (T1), 4 weeks (T2), 8 weeks (T3) and 12 weeks (T4). Participants completed a shuttle run test at T1 and T3. Results: In contrast to previous research in which participation in voluntary sport programs was typically higher among boys, the proportion of males and females nominating for this study was not significantly different to that of the entire grade (2 = 0.75, p = .39). Whereas 27% (40/146) of grade 7 children were identified as “at risk” of social disengagement, 43% of the volunteers for the program (22/51) were in this category, which was significantly more than expected (2 = 68.0, p < .001). The Box’Tag group showed greater improvement in shuttle run performance than controls (F = 4.64, p = .038, d = .69). No significant differences were found for BRUMS or SDQ scores, although the Box’Tag group reported more positive trends than controls for total mood disturbance from T1 to T2. Subjective reports from teachers indicated that several students showed substantial improvements in general behaviour. Discussion: The findings suggest that this new sport program appeals to school age children of both sexes, specifically engages children at risk of social disengagement, may have positive effects on aerobic fitness and mood, and for some students may yield overall behavioural benefits. http://dx.doi.org/10.1016/j.jsams.2012.11.285 283 After school physical activity intervention: Changes and challenges over a three-year-period A. Pienaar ∗ School of Biokinetics, Recreation and Sport Science, North West University, Potchefstroom Campus Background: Researchers report declining trends in PA among adolescents. Those living in low SES environments are also hampered by additional constraints to be active. This study aimed to determine the PA levels and patterns of adolescents after participating in an after school physical activity (PA) intervention study over a 3-yr period. Methods: 309 black adolescents (158 boys, 211 girls) from a disadvantaged environment in South Africa, (M = 14.9 ± 1.4 years boys; 14.3 ± 1.4 years girls) participated in the study. An intervention group participated in an after school health related PA intervention (N = 282) for two years, without any PA intervention in the 3rd year of the study, and was then compared to a control group (N = 87) who received no PA intervention. Final measurements were taken at the end of the 3rd year of the study when no PA intervention took place. Multi-level modelling (repeated measures analysis of co-variance (ANCOVA) and repeated measures analysis of variance (ANOVA) over time, with a Bonferroni post hoc test were used to analyse the data. Week and weekend PA levels and patterns were analysed separately.
S118
Thursday 1 November Papers / Journal of Science and Medicine in Sport 15 (2013) S34–S126
Results: The results showed similar mean PA levels among the two groups of boys (p > 0.05) during baseline, with a significantly higher mean level of PA after 3 years in the intervention group (p < 0.05). Baseline measurements for girls indicated statistically significant mean differences during the week and the weekend, although these differences were not significant during the final measurements three years later. Boys and girls (excluding the intervention group of boys), showed a tendency of declining mean PA over the 3 year period. The PA intervention showed a stabilising effect on the mean PA levels and contributed to more active choices among the intervention group of boys, especially over weekends. Conclusions: Participation in similar PA interventions is recommended for adolescent boys, with adaptations to the content of such PA programs for girls. Such interventions should however be part of the school day, because adolescents living in disadvantaged environments have among other various barriers after school to overcome to be active, which should be addressed by health practitioners to improve the health benefits of such programs.
22%) than in the control group (boys 21%, girls 40%, combined 31%), with p = 0.03 for the combined data. Intervention teachers included more specific fitness work than control classes, mainly in the form of muscular strength and endurance (7 min v 1 min, p < 0.001) associated with dynamic and static postural challenges. Intervention classes also involved more moderate and vigorous physical activity (17 min v 10 min, p < 0.001), but there was no evidence of any four-year intervention effect on daily steps, CRF or %BF. Discussion: By the age of 12, IR had increased to levels of concern in more than a quarter of these apparently healthy children, but well-designed PE attenuated the increase. Given that attention to risk factors during childhood and adolescence is likely to reduce the risk of chronic disease in adults, our data show that primary school PE can play an important role in early preventative medicine.
http://dx.doi.org/10.1016/j.jsams.2012.11.286
Short-interval intracortical inhibition is not affected by varying the complexity of an isometric task in biceps brachii muscle
284 Can physical education improve insulin resistance in healthy boys and girls? The LOOK study Telford 1,∗ ,
Cunningham 2 ,
Daly 3 ,
Telford 4 ,
Olive 5 ,
R. R. R. R. L. A. Lafferty 6 , J. Potter 7 , P. Hickman 7 , E. Southcott 7 , W. Abhayaratna 1 1
Clinical Trials Unit Canberra Hospital and Medical School, Australian National University 2 Fenner School of Environment and Society, Australian National University 3 Centre for Physical Activity and Nutrition Research, Deakin University 4 Centre for Research and Action in Public Health, University of Canberra 5 Department of Psychology, Australian National University 6 Paediatrics and Child Health, Canberra Hospital and Medical School, Australian National University 7 ACT Pathology and Medical School, Australian National University Introduction: With low physical activity (PA) and cardiorespiratory fitness (CRF) in childhood being risk factors for insulin resistance (IR) and type 2 diabetes in adulthood, physical education (PE) in schools provides an ideal opportunity to introduce an early preventative strategy. However there is no evidence to date that primary (elementary) school-based PE can improve IR. Methods: Participants in this 4-year cluster-randomized intervention study were 229 boys and 239 girls in grade 2, initially 8.1 (SD 0.31) years, from 29 primary schools. The curriculum prescribed 150 min/week PE from general classroom teachers, but in 13 schools 100 min/week was replaced with two classes of an intervention program conducted by specialist PE teachers from the not for profit Bluearth Foundation. The remaining schools formed the control. The System of Fitness Instruction Time (SOFIT) was used to compare class activities. Measurements in grades 2, 4 and 6 included fasting blood glucose and insulin for calculation of the homeostatic model of insulin resistance (HOMA-IR), percent body fat (%BF, DXA), PA (7 day pedometers and accelerometers), CRF (multistage run) and pubertal development (Tanner stage selfassessment) and socioeconomic status. Results: With no group differences at baseline, by grade 6 the intervention had lowered IR by 14% (95% CI 1–31) in the boys and 9% (5–26) in the girls. Also by grade 6, the percentage of children with IR greater than 3, a published cut-off point for paediatric metabolic risk, was lower in the intervention (boys 12%, girls 32% combined
http://dx.doi.org/10.1016/j.jsams.2012.11.287 285
D. Kidgell ∗ , M. Leung, C. Brandner, M. Spittle, A. Weier, T. Rantalanen Deakin University Introduction: There is considerable evidence that the excitability of neural networks involved in motor control is modulated in a task-dependant manner. At the level of the primary motor cortex (M1), corticomotoneurons have been shown to be more active during complex tasks. These changes in neural excitability are an adaptive response to the requirements of the motor task. However, the effect of varying the difficulty or complexity of the same task on the excitability of neural circuits is less understood, despite the importance of task-complexity in the rehabilitation of fine motor skill. The purpose of this study was to determine whether taskdependant differences in motor cortical network excitability occur when varying the complexity, via visuomotor feedback of an elbow flexion task. Methods: Focal transcranial magnetic stimulation (TMS) was used to measure corticospinal excitability and short-intervalintracortical inhibition (SICI) of the contralateral biceps brachii (BB) in 10 healthy subjects, performing two isometric tasks of differing visuomotor demand at 5, 20 & 40% of maximum voluntary contraction force (MVC). To produce two tasks with differing visuomotor demand, the scaling of the on-line torque trace was modified. Results: Corticospinal excitability did not differ between tasks (p > 0.05), did differ between torque levels (p < 0.05) and there was no task x torque level interaction effect (p > 0.05). SICI did not differ between tasks (p > 0.05), did between torque levels (p < 0.05) and there was no task x torque level interaction (p > 0.05). Discussion: This study shows that the excitability of intracortical neural networks namely, intracortical inhibition; is reduced during increasing levels of torque production. The present findings demonstrate the influence of target torque levels on disinhibition of corticospinal neurons (i.e. increase M1 excitability), modulated by neurons responsible for SICI. Conclusion: This study has demonstrated that intracortical inhibition is reduced during graded voluntary muscle action, which suggests that force production is modulated by neurons confined to the M1. Interestingly, the level of inhibition is not altered when varying the difficulty of the same task. This finding, which is in contrast to findings on lower arm musculature, suggests that SICI is more markedly modulated by force gradation than by task visuomotor demands at least in the BB muscle. These findings have