Melvyn Hillsdon

Physical activity and older adults: a review of health benefits and the effectiveness of interventions

The purpose of this multidisciplinary review paper is to critically review evidence from descriptive, efficacy and effectiveness studies concerned with physical activity and older people. Both levels of fitness (aerobic power, strength, flexibility and functional capability) and measures of physical activity involvement decline with age, and the extent to which this is due to a biological ageing processes or disuse (physical inactivity) is critically examined. The review will consider the evidence for a causal relationship between sedentary behaviour/physical activity programmes and cardiovascular, musculoskeletal and psycho-social health, independent living and health-related quality of life into old age. The review also considers the effectiveness of different physical activity interventions for older people and issues relating to cost-effectiveness. The implications for future policy in terms of research, health care services, and education and training are briefly discussed.

The relationship of physical activity and overweight to objectively measured green space accessibility and use.

This study examines the association between objectively measured access to green space, frequency of green space use, physical activity, and the probability of being overweight or obese in the city of Bristol, England. Data from the 2005 Bristol Quality of Life in your Neighbourhood survey for 6821 adults were combined with a comprehensive GIS database of neighbourhood and green space characteristics. A range of green space accessibility measures were computed. Associations between accessibility and the odds of respondents achieving a recommended 30min or more of moderate activity five times a week, or being overweight or obese, were examined using logistic regression. Results showed that the reported frequency of green space use declined with increasing distance. The study also found that respondents living closest to the type of green space classified as a Formal park were more likely to achieve the physical activity recommendation and less likely to be overweight or obese. The association with physical activity, but not with overweight or obesity, remained after adjustment for respondent characteristics, area deprivation, and a range of characteristics of the neighbourhood environment. The findings suggest that the provision of good access to green spaces in urban areas may help promote population physical activity.

Physical activity and obesity.

This paper was commissioned by the Foresight programme of the Office of Science and Innovation, Department of Trade and Industry

Environmental perceptions and walking in English adults.

Study objective: To examine the relation between adults’ perceptions of the social and physical environment and their self reported walking behaviour. Design: Cross sectional survey. Setting: England. Participants: A national sample of 4265 adults aged 16–74 years. Main outcome measures: Self reported walking behaviour was categorised into two dichotomous variables: (a) any reported walking in past four weeks, (b) reported walking ⩾150 minutes per week in the past four weeks. Perceptions of the social environment covered safety of walking alone and social support for walking. Perceptions of the physical environment covered attractiveness of local area for walking, access to shops, leisure centres, parks, cycle paths, and traffic density. Main results: In women, perceived safety of walking during the day (OR =  0.53; 95% CI: 0.31 to 0.88), and no shop within walking distance (OR = 0.72; 95% CI: 0.52 to 0.99) were associated with any reported walking occasions. Perceptions of the environment were not related to women walking ⩾150 min/week. In men, having a park within walking distance was associated with walking ⩾150 min/week (OR =  2.22; 95% CI: 1.18 to 4.35). No other significant associations were found. Conclusions: Women seem to be more concerned about walking for utility and in safety. Men are more likely to walk ⩾150 min/week if they have access to a local park but their walking is not influenced by concerns about safety. Future research should focus on the relation between objective measures rather than perceptions of the environment and physical activity.

A systematic review of physical activity promotion strategies.

We have reviewed randomised controlled trials of physical activity promotion to provide recent and reliable information on the effectiveness of physical activity promotion. Computerised databases and references of references were searched. Experts were contacted and asked for information about existing work. Studies assessed were randomised controlled trials of healthy, free living, adult subjects, where exercise behaviour was the dependent variable. Eleven trials were identified. No United Kingdom based studies were found. Interventions that encourage walking and do not require attendance at a facility are most likely to lead to sustainable increases in overall physical activity. Brisk walking has the greatest potential for increasing overall activity levels of a sedentary population and meeting current public health recommendations. The small number of trials limits the strength of any conclusions and highlights the need for more research.

Randomised controlled trials of physical activity promotion in free living populations: a review.

OBJECTIVES--To review evidence on the effectiveness of trials of physical activity promotion in healthy, free living adults. To identify the more effective intervention programmes. METHODS--Computerised databases and references were searched. Experts were contacted and asked for information about existing work. INCLUSION CRITERIA--Randomised controlled trials of healthy, free living adult subjects, where exercise behaviour was the dependent variable were included. CONCLUSIONS--Ten trials were identified. The small number of trials limits the strength of any conclusions and highlights the need for more research. No UK based studies were found. Previously sedentary adults can increase activity levels and sustain them. Promotion of these changes requires personal instruction, continued support, and exercise of moderate intensity which does not depend on attendance at a facility. The exercise should be easily included into an existing lifestyle and should be enjoyable. Walking is the exercise most likely to fulfil these criteria.

Effect of exercise referral schemes in primary care on physical activity and improving health outcomes: systematic review and meta-analysis.

Objective To assess the impact of exercise referral schemes on physical activity and health outcomes. Design Systematic review and meta-analysis. Data sources Medline, Embase, PsycINFO, Cochrane Library, ISI Web of Science, SPORTDiscus, and ongoing trial registries up to October 2009. We also checked study references. Study selection Design: randomised controlled trials or non-randomised controlled (cluster or individual) studies published in peer review journals. Population: sedentary individuals with or without medical diagnosis. Exercise referral schemes defined as: clear referrals by primary care professionals to third party service providers to increase physical activity or exercise, physical activity or exercise programmes tailored to individuals, and initial assessment and monitoring throughout programmes. Comparators: usual care, no intervention, or alternative exercise referral schemes. Results Eight randomised controlled trials met the inclusion criteria, comparing exercise referral schemes with usual care (six trials), alternative physical activity intervention (two), and an exercise referral scheme plus a self determination theory intervention (one). Compared with usual care, follow-up data for exercise referral schemes showed an increased number of participants who achieved 90-150 minutes of physical activity of at least moderate intensity per week (pooled relative risk 1.16, 95% confidence intervals 1.03 to 1.30) and a reduced level of depression (pooled standardised mean difference −0.82, −1.28 to −0.35). Evidence of a between group difference in physical activity of moderate or vigorous intensity or in other health outcomes was inconsistent at follow-up. We did not find any difference in outcomes between exercise referral schemes and the other two comparator groups. None of the included trials separately reported outcomes in individuals with specific medical diagnoses. Substantial heterogeneity in the quality and nature of the exercise referral schemes across studies might have contributed to the inconsistency in outcome findings. Conclusions Considerable uncertainty remains as to the effectiveness of exercise referral schemes for increasing physical activity, fitness, or health indicators, or whether they are an efficient use of resources for sedentary people with or without a medical diagnosis.

Effects of physical activity on cognitive functioning in middle age: evidence from the Whitehall II prospective cohort study.

OBJECTIVES We examined the association between physical activity and cognitive functioning in middle age. METHODS Data were derived from a prospective occupational cohort study of 10308 civil servants aged 35-55 years at baseline (phase 1; 1985-1988). Physical activity level, categorized as low, medium, or high, was assessed at phases 1, 3 (1991-1994), and 5 (1997-1999). Cognitive functioning was tested at phase 5, when respondents were 46-68 years old. RESULTS In both prospective (odds ratio [OR] = 1.65; 95% confidence interval [CI]=1.30, 2.10) and cross-sectional (OR=1.79; 95% CI=1.38, 2.32) analyses, low levels of physical activity were a risk factor for poor performance on a measure of fluid intelligence. Analyses aimed at assessing cumulative effects (summary of physical activity levels at the 3 time points) showed a graded linear relationship with fluid intelligence, with persistently low levels of physical activity being particularly harmful (OR=2.21; 95% CI=1.37, 3.57). CONCLUSIONS Low levels of physical activity are a risk factor for cognitive functioning in middle age, fluid intelligence in particular.

Patterns of GPS measured time outdoors after school and objective physical activity in English children: the PEACH project

BackgroundObservational studies have shown a positive association between time outdoors and physical activity in children. Time outdoors may be a feasible intervention target to increase the physical activity of youth, but methods are required to accurately measure time spent outdoors in a range of locations and over a sustained period. The Global Positioning System (GPS) provides precise location data and can be used to identify when an individual is outdoors. The aim of this study was to investigate whether GPS data recorded outdoors were associated with objectively measured physical activity.MethodsParticipants were 1010 children (11.0 ± 0.4 years) recruited from 23 urban primary schools in South West England, measured between September 2006 and July 2008. Physical activity was measured by accelerometry (Actigraph GT1M) and children wore a GPS receiver (Garmin Foretrex 201) after school on four weekdays to record time outdoors. Accelerometer and GPS data were recorded at 10 second epochs and were combined to describe patterns of physical activity when both a GPS and accelerometer record were present (outdoors) and when there was accelerometer data only (indoors). ANOVA was used to investigate gender and seasonal differences in the patterns of outdoor and indoor physical activity, and linear regression was used to examine the cross-sectional associations between GPS-measured time outdoors and physical activity.ResultsGPS-measured time outdoors was a significant independent predictor of childrens physical activity after adjustment for potential confounding factors. Physical activity was more than 2.5 fold higher outdoors than indoors (1345.8 ± 907.3 vs 508.9 ± 282.9 counts per minute; F = 783.2, p < .001). Overall, children recorded 41.7 ± 46.1 minutes outdoors between 3.30 pm and 8.30 pm, with more time spent outdoors in the summer months (p < .001). There was no gender difference in time spent outdoors. Physical activity outdoors was higher in the summer than the winter (p < .001), whilst there was no seasonal variation in physical activity indoors.ConclusionsDuration of GPS recording is positively associated with objectively measured physical activity and is sensitive to seasonal differences. Minute by minute patterning of GPS and physical activity data is feasible and may be a useful tool to investigate environmental influences on childrens physical activity and to identify opportunities for intervention.

Mapping the walk to school using accelerometry combined with a global positioning system.

BACKGROUND Walking to school is associated with higher levels of physical activity, but the contribution of the journey itself to physical activity before school is unknown. PURPOSE This study combined accelerometer and GPS data to investigate the level and location of physical activity in children walking to school. METHODS Participants were 137 children (aged 11.3 + or - 0.3 years) from London, England, measured in June-July 2006. Physical activity was measured by accelerometry, and location was determined with a GPS receiver. Travel mode was self-reported. Accelerometer and GPS data were time-matched to provide activity level and location for each 10-second epoch where both were available. Journeys were mapped in a GIS. RESULTS Mean accelerometer counts per minute before school (8:00 am to 9:00 am) were 43% higher in those who walked to school than those traveling by car (878.8 + or - 387.6 vs 608.7 + or - 264.1 counts per minute [cpm], p<0.001). Eleven percent (4.5 minutes) of daily moderate to vigorous physical activity (MVPA) occurred in this hour, with walkers recording 2.1 minutes more than car travelers (p = 0.004). Children followed direct routes between home and the school playground. Total activity during the walk to school was twice that in the playground (2131.3 + or - 1170.7 vs 1089.7 + or - 938.6 cpm, p<0.001), with the journey contributing three times as much MVPA as time in the playground. CONCLUSIONS Our results provide evidence that the journey to school is purposeful and contributes to higher total physical activity and MVPA in children. Combining accelerometer and GPS data may aid our understanding of the environmental context of physical activity.