Habitual physical activity modulates cardiometabolic health in long-term testicular cancer survivors

PURPOSES

Physical activity (PA) may mitigate late cardiometabolic toxicity of cisplatin-based chemotherapy in testicular germ cell tumor (TGCT) long-term survivors. In this cross-sectional study, we evaluated the effects of habitual PA on metabolic syndrome (MetS) prevalence, and on the markers of cardiometabolic health and chronic inflammation in a population of long-term TGCT survivors.

METHODS

MetS prevalence was evaluated, and habitual PA was assessed using Baecke's habitual PA questionnaire in TGCT survivors (n=195, age=41.1±8.1years, 11.7±5.2years post-therapy) and healthy male controls (n=41, age=38.2±8.8years). Participants were stratified into low- and high-PA groups based on median values. Differences were examined between low- and high-PA groups (in the entire sample, TGCT survivor sub-samples differing in disease stage, and healthy controls), and between TGCT survivors and controls. Next, TGCT survivors were stratified into age- and BMI-matched sub-groups based on post-treatment time (5-15/15/30years) and number of chemotherapy cycles (≤3/>3), allowing us to detect age- and BMI-independent effects of habitual PA on cardiometabolic health in the given TGCT survivor sub-populations. A correlation matrix of habitual PA and sport activity with cardiometabolic and pro-inflammatory markers was generated.

RESULTS

TGCT survivors had higher MetS prevalence than controls. Patients with high habitual PA had lower waist circumference and Systemic Inflammation Index. Habitual PA scores correlated positively with HDL-cholesterol and negatively with waist circumference and atherogenic risk. Furthermore, cardiometabolic benefits of habitual PA were more pronounced in patients with disease stages 1 and 2. Effects of habitual PA on patients sub-populations stratified by chemotherapy dose and post-treatment time clearly showed that higher levels of habitual PA were associated with lower numbers of MetS components, except for patients who received more than 3 chemotherapy cycles and were examined more than15 years post-therapy.

CONCLUSIONS

Higher levels of habitual PA effectively mitigated cardiometabolic toxicity in TGCT survivors. Patients with higher cumulative doses of chemotherapy may need structured exercise interventions involving higher-intensity physical activity to achieve significant improvements in cardiometabolic health.

Greater habitual moderate-to-vigorous physical activity is associated with better executive function and higher prefrontal oxygenation in older adults

International physical activity guidelines recommend that older adults accumulate 150 min/week of moderate-vigorous physical activity (MVPA). It is unclear whether meeting this recommendation is associated with better higher-order cognitive functions and if so, what are the neurophysiological mechanisms responsible for such a relationship. We tested the hypothesis that meeting MVPA guidelines is associated with better executive function in older adults, and explored if greater increases in prefrontal cortex oxygenation are implicated. Older adults who did (active, n = 19; 251 ± 79 min/week) or who did not (inactive, n = 16; 89 ± 33 min/week) achieve activity guidelines were compared. Executive function was determined via a computerized Stroop task while changes in left prefrontal cortex oxygenation (ΔO₂Hb) were measured with functional near-infrared spectroscopy. Aerobic fitness ([Formula: see text] ₂peak) was determined using a graded, maximal cycle ergometry test. MVPA and sedentary time were objectively assessed over 5 days. Both groups had similar (both, P > 0.11) levels of aerobic fitness (24.9 ± 8.9 vs. 20.9 ± 5.6 ml/kg/min) and sedentary time (529 ± 60 vs. 571 ± 90 min/day). The active group had faster reaction times (1193 ± 230 vs. 1377 ± 239 ms, P < 0.001) and greater increases in prefrontal cortex ΔO₂Hb (9.4 ± 5.6 a.u vs. 5.8 ± 3.4 a.u, P = 0.04) during the most executively demanding Stroop condition than the Inactive group. Weekly MVPA was negatively correlated to executive function reaction times (r =  - 0.37, P = 0.03) but positively correlated to the ΔO₂Hb responses (r = 0.39. P = 0.02) during the executive task. In older adults, meeting MVPA guidelines is associated with better executive function and larger increases in cerebral oxygenation among older adults.

Association between habitual physical activity (HPA) and sleep quality in patients with cystic fibrosis

PURPOSE

Sleep disturbances and poor sleep quality are known to be present in patients with CF. Regular physical activity plays an important role in the treatment of CF patients due to its positive influence on progression of disease and quality of life. The aim of this work is to create a home-based sleep and activity profile and to investigate the influence of habitual physical activity (HPA) on sleep quality in children, adolescents, and adults with CF.

METHODS

A total of 109 CF patients (64 male, mean age 22.7 ± 12.0 years; mean ppFEV1 63.0 ± 26.7) were equipped with an actigraph for a home-based collection of data on sleep and activity over 4 weeks.

RESULTS

Age, FEV1, and BMI affect sleep and activity in CF patients. Especially younger age and higher FEV1 show a great influence on certain aspects of sleep (SE, TST, TIB, WASO, # of awakenings) and activity and its different intensities. General HPA does not affect sleep, but there is a strong correlation between times spent in vigorous to very vigorous intensities and better sleep quality.

CONCLUSION

Besides younger age and higher FEV1, daily activity in higher intensities influences sleeping behavior of CF patients in a positive way. Patients with poor sleep quality and sleep disturbances possibly benefit from an intensification of physical activity in the home environment. TRAIL REGISTRATION: number: 14-6117-BO (University Duisburg-Essen) and NCT03518697 (clinical trials).

Does fine particulate matter (PM2.5) affect the benefits of habitual physical activity on lung function in adults: a longitudinal cohort study

BACKGROUND

Physical activity (PA) increases a person's inhalation of air pollutants due to greater ventilation, possibly leading to larger adverse health effects. This study aims to investigate the combined effects of long-term exposure to fine particulate matter (PM_2.5) and habitual PA on lung function in adults.

METHODS

This was a longitudinal cohort study that included 278,065 Taiwan residents with an age of 20 years old or above who joined a standard medical screening programme between 2001 and 2014. Each participant received at least one medical examination (including spirometric, blood, and urinary tests and a standard self-administered questionnaire survey) during the study period. We estimated the 2-year average PM_2.5 concentrations at each participant's address using a new physical model based on observational data. Information on the participants' PA was collected using the standard self-administrated questionnaire. Generalised linear mixed models were used to investigate the combined effects of PM_2.5 and PA on pulmonary function. We also performed stratified analyses by different levels of PM_2.5 exposure and habitual PA.

RESULTS

Each 10 MET-h increase in PA was associated with a higher level of 0.20%, 0.16%, and 0.19% in forced vital capacity (FVC), forced expiratory volume in the first second (FEV₁), and maximum mid-expiratory flow (MMEF), respectively, after adjusting for PM_2.5 exposure and a wide range of covariates including age, sex education, body mass index, lifestyles, and health conditions. Each 10 μg/m³ increase in PM_2.5 was associated with a lower FVC, FEV₁, and MMEF (2.43%, 2.78% and 3.10%, respectively). Negative interactions were observed, and PM_2.5 exposure was associated with a greater reduction in lung function among the participants with higher PA levels.

CONCLUSIONS

We found significant negative interaction effects between long-term exposure to PM_2.5 and habitual PA, suggesting that the increased intake of PM_2.5 due to PA may attenuate the benefits of habitual PA on lung function. However, the PA benefits generally remained stable at different stratum of PM_2.5 in the stratified analyses, and habitual PA may still be recommended to people residing in relatively polluted regions.

Lower physical activity is associated with daytime sleepiness in children aged 9-12 years

This study clarified the prevalence of daytime sleepiness in fourth-, fifth-, and sixth-grade children and examined the association between physical activity (PA) and daytime sleepiness in children aged 9-12 years. This cross-sectional study included 314 children (mean age ± standard deviation: 10.5 ± 1.0 years; male: 52.9%) enrolled in two public elementary schools in Kobe, Japan. PA was assessed using the Physical Activity Questionnaire for Older Children. The outcome was self-reported daytime sleepiness. The prevalence of daytime sleepiness in fourth-, fifth-, and sixth-grade children were 10.8%, 25.2%, and 28.6%, respectively. In univariate analysis, subjects with reported daytime sleepiness had lower PA levels than those without daytime sleepiness (odds ratio (OR) = .67; 95% confidence interval (CI) = .47-.95). Multiple logistic regression analysis demonstrated that lower PA was significantly associated with daytime sleepiness after adjusting for multiple confounders (OR = .54; 95% CI = .37-.81). The prevalence of daytime sleepiness in fifth and sixth grades was higher than fourth grade. Furthermore, this study clarified the significant association between PA and daytime sleepiness and suggested that PA could be one of the factors to prevent daytime sleepiness in children aged 9-12 years.

Understanding parent perceptions of healthy physical activity for their child with a chronic medical condition: A cross-sectional study

Objective

We sought to determine the prevalence of, and identify factors associated with, parent questions about physical activity for their child with a chronic cardiac, respiratory, or rheumatologic condition.

Methods

This cross-sectional study of 56 children (32 [57%] female), 3 to 18 years of age, with chronic cardiac (n=21), respiratory (n=18), or rheumatologic (n=17) conditions involved a parent questionnaire about their child's physical activity participation and measurement of the child's activity with an omni-directional accelerometer for 1 week.

Results

Parents of 20 (36%) children had at least one question about their child's physical activity participation, and the prevalence of questions did not vary by age (Wald chi square = 0.77, P=0.38), gender (Wald chi square = 0.11, P=0.74), or clinic (Wald chi square = 1.77, P=0.41). Parent questions were associated (P = 0.04) with lower levels of activity for boys (95% confidence interval [CI] for estimated marginal means: With questions: 197, 395; Without questions: 346, 500) and higher levels of activity for girls (95% CI for estimated marginal means: With questions: 268, 448; Without questions: 239, 369). A multivariable logistic regression model found that parents with questions had higher odds of having a child who was less well (odds ratio [OR]=19.9 for unwell, OR=5.6 for generally well with some symptoms versus well and asymptomatic) and had a history of cardiac arrhythmia (OR=7.6).

Conclusions

Over one-third of parents reported having questions about physical activity for their child with a chronic medical condition, suggesting substantial uncertainty even among children reported as active. Presence of parent uncertainty is associated with parent reports of the child being unwell or a history of cardiac arrhythmia. By asking parents if they have questions about their child's activity, health care professionals may be better able to identify inactive boys and overprotective attitudes toward active girls.

Machine learning algorithms for activity recognition in ambulant children and adolescents with cerebral palsy

BACKGROUND

Cerebral palsy (CP) is the most common physical disability among children (2.5 to 3.6 cases per 1000 live births). Inadequate physical activity (PA) is a major problem effecting the health and well-being of children with CP. Practical, yet accurate measures of PA are needed to evaluate the effectiveness of surgical and therapy-based interventions to increase PA. Accelerometer-based motion sensors have become the standard for objectively measuring PA in children and adolescents; however, current methods for estimating physical activity intensity in children with CP are associated with significant error and may dramatically underestimate HPA in children with more severe mobility limitations. Machine learning (ML) models that first classify the PA type and then predict PA intensity or energy expenditure using activity specific regression equations may be more accurate than standalone regression models. However, the feasibility and validity of ML methods has not been explored in youth with CP. Therefore, the purpose of this study was to develop and test ML models for the automatic identification of PA type in ambulant children with CP.

METHODS

Twenty two children and adolescents (mean age: 12.8 ± 2.9 y) with CP classified at GMFCS Levels I to III completed 7 activity trials while wearing an ActiGraph GT3X+ accelerometer on the hip and wrist. Trials were categorised as sedentary (SED), standing utilitarian movements (SUM), comfortable walking (CW), and brisk walking (BW). Random forest (RF), support vector machine (SVM), and binary decision tree (BDT) classifiers were trained with features extracted from the vector magnitude (VM) of the raw acceleration signal using 10 s non-overlapping windows. Performance was evaluated using leave-one-subject out cross validation.

RESULTS

SVM (82.0-89.0%) and RF (82.6-88.8%) provided significantly better classification accuracy than BDT (76.1-86.2%). Hip (82.7-85.5%) and wrist (76.1-82.6%) classifiers exhibited comparable prediction accuracy, while the combined hip and wrist (86.2-89.0%) classifiers achieved the best overall performance. For all classifiers, recognition accuracy was excellent for SED (94.1-97.9%), good to excellent for SUM (74.0-96.6%) and brisk walking (71.5-86.0%), and modest for comfortable walking (47.6-70.4%). When comfortable and brisk walking were combined into a single walking class, recognition accuracy ranged from 90.3 to 96.5%.

CONCLUSIONS

ML methods provided acceptable classification accuracy for detection of a range of activities commonly performed by ambulatory children with CP. The resultant models can help clinicians more effectively monitor bouts of brisk walking in the community. The results indicate that 2-step models that first classify PA type and then predict energy expenditure using activity specific regression equations are worthy of exploration in this patient group.

Variability and reliability study of overall physical activity and activity intensity levels using 24 h-accelerometry-assessed data

Background

24 h-accelerometry is now used to objectively assess physical activity (PA) in many observational studies like the German National Cohort; however, PA variability, observational time needed to estimate habitual PA, and reliability are unclear.

Methods

We assessed 24 h-PA of 50 participants using triaxial accelerometers (ActiGraph GT3X+) over 2 weeks. Variability of overall PA and different PA intensities (time in inactivity and in low intensity, moderate, vigorous, and very vigorous PA) between days of assessment or days of the week was quantified using linear mixed-effects and random effects models. We calculated the required number of days to estimate PA, and calculated PA reliability using intraclass correlation coefficients.

Results

Between- and within-person variance accounted for 34.4–45.5% and 54.5–65.6%, respectively, of total variance in overall PA and PA intensities over the 2 weeks. Overall PA and times in low intensity, moderate, and vigorous PA decreased slightly over the first 3 days of assessment. Overall PA (p = 0.03), time in inactivity (p = 0.003), in low intensity PA (p = 0.001), in moderate PA (p = 0.02), and in vigorous PA (p = 0.04) slightly differed between days of the week, being highest on Wednesday and Friday and lowest on Sunday and Monday, with apparent differences between Saturday and Sunday. In nested random models, the day of the week accounted for < 19% of total variance in the PA parameters. On average, the required number of days to estimate habitual PA was around 1 week, being 7 for overall PA and ranging from 6 to 9 for the PA intensities. Week-to-week reliability was good (intraclass correlation coefficients, range, 0.68–0.82).

Conclusions

Individual PA, as assessed using 24 h-accelerometry, is highly variable between days, but the day of assessment or the day of the week explain only small parts of this variance. Our data indicate that 1 week of assessment is necessary for reliable estimation of habitual PA.

Electronic supplementary material

The online version of this article (10.1186/s12889-018-5415-8) contains supplementary material, which is available to authorized users.

Quality of life and habitual physical activity in children with cerebral palsy aged 5 years: A cross-sectional study

OBJECTIVE

To compare quality of life (QOL) according to ambulatory status and to investigate association with habitual physical activity (HPA) in children with cerebral palsy (CP) aged 5 years.

METHODS

Fifty-eight participants were classified using Gross Motor Function Classification System (GMFCS) as level I = 33, II = 8, III = 6, IV = 3 and V = 8 and assessed for motor function using 66-item Gross Motor Function Measure (GMFM-66). Participants wore an ActiGraph^® triaxial accelerometer for 3 days to measure HPA. Parents completed the parent proxy Cerebral Palsy Quality of Life questionnaire for Children (CP QOL-Child). Linear regression analyses were performed.

RESULTS

Ambulant children with CP (GMFCS I-III) had better parent-reported QOL than non-ambulant children (GMFCS IV-V) in domains of feelings about functioning (mean difference (MD) = 20.0; 95% confidence interval (CI) = 11.7, 28.2), participation and physical health (MD = 14.5; 95%CI = 4.7, 24.4), and emotional well-being and self-esteem (MD = 12.5; 95%CI = 4.8, 20.1). HPA was not associated with QOL domains after controlling for motor function. GMFM scores accounted for 39% of variation for feelings about functioning domain (MD = 0.4; 95%CI = 0.2, 0.6).

CONCLUSIONS

In children with CP aged 5 years, HPA was not associated with parent-reported QOL. Gross motor function contributed to QOL domains of feelings about functioning.

Real-world walking in multiple sclerosis: Separating capacity from behavior

BACKGROUND

Habitual physical activity (HPA) measurement addresses the impact of MS on real-world walking, yet its interpretation is confounded by the competing influences of MS-associated walking capacity and physical activity behaviors.

OBJECTIVE

To develop specific measures of MS-associated walking capacity through statistically sophisticated HPA analysis, thereby more precisely defining the real-world impact of disease.

METHODS

Eighty-eight MS and 38 control subjects completed timed walks and patient-reported outcomes in clinic, then wore an accelerometer for 7days. HPA was analyzed with several new statistics, including the maximum step rate (MSR) and habitual walking step rate (HWSR), along with conventional methods, including average daily steps. HPA statistics were validated using clinical walking outcomes.

RESULTS

The six-minute walk (6MW) step rate correlated most strongly with MSR (r=0.863, p<10^-25) and HWSR (r=0.815, p<10^-11) rather than average daily steps (r=0.676, p<10^-11). The combination of MSR and HWSR correlated more strongly with the 6MW step rate than either measure alone (r=0.884, p<10^-14). The MSR overestimated the 6MW step rate (μ=10.4, p<10^-7), whereas the HWSR underestimated it (μ=-18.2, p<10^-19).

CONCLUSIONS

Conventional HPA statistics are poor measures of capacity due to variability in activity behaviors. The MSR and HWSR are valid, specific measures of real-world capacity which capture subjects' highest step rate and preferred step rate, respectively.

Impact of physical activity level and dietary fat content on passive overconsumption of energy in non-obese adults

Background

Passive overconsumption is the increase in energy intake driven by the high-fat energy-dense food environment. This can be explained in part because dietary fat has a weaker effect on satiation (i.e. process that terminates feeding). Habitually active individuals show improved satiety (i.e. process involved in post-meal suppression of hunger) but any improvement in satiation is unknown. Here we examined whether habitual physical activity mitigates passive overconsumption through enhanced satiation in response to a high-fat meal.

Methods

Twenty-one non-obese individuals with high levels of physical activity (HiPA) and 19 individuals with low levels of physical activity (LoPA) matched for body mass index (mean = 22.8 kg/m²) were recruited. Passive overconsumption was assessed by comparing ad libitum energy intake from covertly manipulated high-fat (HFAT; 50% fat) or high-carbohydrate (HCHO; 70% carbohydrate) meals in a randomized crossover design. Habitual physical activity was assessed using SenseWear accelerometers (SWA). Body composition, resting metabolic rate, eating behaviour traits, fasting appetite-related peptides and hedonic food reward were also measured.

Results

In the whole sample, passive overconsumption was observed with greater energy intake at HFAT compared to HCHO (p < 0.01), without any differences between activity groups (p > 0.05). SWA confirmed that HiPA were more active than LoPA (p < 0.01). HiPA had lower body fat and greater fat-free mass than LoPA (p < 0.05 for both) but did not differ in resting metabolic rate, eating behaviour traits, appetite-related peptides or food reward (p > 0.05 for all).

Conclusions

Non-obese individuals with high or low physical activity levels but matched for BMI showed similar susceptibility to passive overconsumption when consuming an ad libitum high-fat compared to a high-carbohydrate meal. This occurred despite increased total daily energy expenditure and improved body composition in HiPA. Greater differences in body composition and/or physical activity levels may be required to impact on satiation.

Electronic supplementary material

The online version of this article (doi:10.1186/s12966-017-0473-3) contains supplementary material, which is available to authorized users.

Low socio-economic environmental determinants of children's physical activity in Coventry, UK: A Qualitative study in parents

Background

Children's physical activity (PA) is affected by socio-economic status (SES) and the environment. Children are not fully autonomous in their decision making; parental decisions thus affect how children utilise their surrounding environments for PA. The aim was to examine environmental influences on children's PA from a qualitative perspective in parents from low SES wards in Coventry, UK.

Method

59 parents of children in year 4 (aged 8–9years) completed the ALPHA environmental questionnaire. 16 of these parents took part in focus group discussions examining environmental facilitators and barriers to their child's PA (March–April, 2013).

Results

Emerging themes related to physical (i.e. poor access, safety and quality of the neighbourhood) and social environment (i.e. ‘rough’ neighbourhood due to crime and anti-social behaviour) influences on the PA behaviour of children. The parents believed these environmental factors resulted in the children engaging in greater sedentary activity (watching TV) indoors. The school environment was perceived as a supportive physical environment for children's PA behaviour.

Conclusion

Parent's perceptions of an unsupportive physical and social environment restrict children's opportunities to play outside and be physically active and may lead to increased body fat (BF). Schools provide a supportive environment for children from low SES to be physically active in.

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Qualitative study exploring the effect of parental perceptions on child's physical activity.

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Poor perceptions of the physical and social environment limit children's physical activity.

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Parents' safety concerns limit children's physical activity to indoors.

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Religious practice limits time available for physical activity in Muslim children.

Does body shaping influence brain shape? Habitual physical activity is linked to brain morphology independent of age

OBJECTIVES

Physical activity (PA) was found to influence human brain morphology. However, the impact of PA on brain morphology was mainly demonstrated in seniors. We investigated healthy individuals across a broad age range for the relation between habitual PA and brain morphology.

METHODS

Ninety-five participants (19-82 years) were assessed for self-reported habitual PA with the "Baecke habitual physical activity questionnaire", and T1-weighted magnetic resonance images were evaluated with whole brain voxel based morphometry for gray and white matter volumes and densities.

RESULTS

Regression analyses revealed a positive relation between the extent of physical activity and gray matter volume bilaterally in the anterior hippocampal and parahippocampal gyrus independent of age and gender. Age as well as leisure and locomotion activities were linked to enhanced white matter volumes in the posterior cingulate gyrus and precuneus, suggesting a positive interaction especially in seniors.

CONCLUSIONS

Habitual physical activity is associated with regional volumetric gray and white matter alterations. The positive relation of hippocampal volume and physical activity seems not to be restricted to seniors. Thus, habitual physical activity should be generally considered as an influencing factor in studies investigating medial temporal lobe volume and associated cognitive functions (memory), especially in psychiatric research.

Systematic review of the relationship between habitual physical activity and motor capacity in children with cerebral palsy

Habitual physical activity (HPA) has many benefits for general health. Motor capacity in children with cerebral palsy (CP) can impact on their HPA. This study aimed to systematically review the available literature on the relationship between HPA and motor capacity in children with CP aged 3-12 years for all gross motor functional abilities (GMFCS I-V) compared to typically developing children. Five electronic databases (Pubmed, Cochrane, Embase, Cinahl and Web of Science from 1989 to November, 2013) were searched using keywords "children with cerebral palsy", "physical activity", "motor capacity" and "motor function" including their synonyms and MesH terms. Studies were included if they (i) were conducted in children with CP aged between 3 and 12 years, (ii) assessed HPA or time spent sedentary, (iii) assessed motor capacity in order to evaluate the relationship between HPA and motor capacity. All articles retrieved were reviewed by two independent reviewers and discussed until they reached consensus. Study quality of reporting was evaluated using the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) criteria. Search results identified 864 articles but after review of the title and abstract only 21 articles warranted closer consideration. Ten articles met the strict inclusion criteria as nine articles did not assess HPA and two were conference abstracts. Study quality assessment (STROBE) found nine articles were good quality (≥ 60%) and one was poor quality (55.9%). Participants were mean age 8.4 (SD=2.1) years (range 2-17 years) and included children at all GMFCS levels (3 studies), while seven studies only recruited GMFCS level I-III. HPA measurements were either subjective (Activity Scale for Kids, Dutch Questionnaire of Participation in physical activity and assessment of participation in physical education at school and regular physical activity in leisure time) or objective (StepWatch(®) and ActiGraph(®)7164). Nine studies found that motor capacity was directly associated with HPA, HPA in children with CP with high functional level (GMFCS I) was higher than those with lower functional levels (GMFCS III-V); while one study reported no relationship between HPA and GMFCS level (HPA was measured by questionnaire, a potential limitation). Further studies are required to further elucidate HPA levels (active, sedentary behavior) according to objective motor capacity measures, age and gender to inform healthy lifestyle behavior (active/sedentary) in children with CP.

Low socio-economic environmental determinants of children's physical activity in Coventry, UK: A Qualitative study in parents

BACKGROUND

Children's physical activity (PA) is affected by socio-economic status (SES) and the environment. Children are not fully autonomous in their decision making; parental decisions thus affect how children utilise their surrounding environments for PA. The aim was to examine environmental influences on children's PA from a qualitative perspective in parents from low SES wards in Coventry, UK.

METHOD

59 parents of children in year 4 (aged 8-9years) completed the ALPHA environmental questionnaire. 16 of these parents took part in focus group discussions examining environmental facilitators and barriers to their child's PA (March-April, 2013).

RESULTS

Emerging themes related to physical (i.e. poor access, safety and quality of the neighbourhood) and social environment (i.e. 'rough' neighbourhood due to crime and anti-social behaviour) influences on the PA behaviour of children. The parents believed these environmental factors resulted in the children engaging in greater sedentary activity (watching TV) indoors. The school environment was perceived as a supportive physical environment for children's PA behaviour.

CONCLUSION

Parent's perceptions of an unsupportive physical and social environment restrict children's opportunities to play outside and be physically active and may lead to increased body fat (BF). Schools provide a supportive environment for children from low SES to be physically active in.