title: Leisure Time, Occupational, and Commuting Physical Activity and the Risk of Stroke Good intentions and received wisdom are not good enough: the need for controlled trials in public health “Walk in to Work Out”: a randomised controlled trial of a self help intervention to promote active commuting Physical activity and cause-specific mortality in men: Further evidence from the Whitehall study Walking to Work and the Risk for Hypertension in Men: The Osaka Health Survey All-cause mortality associated with physical activity during leisure time, work, sports, and cycling to work. The mode of school transportation in pre-pubertal children does not influence the accrual of bone mineral or the gain in bone size - two year prospective data from the paediatric osteoporosis preventive (POP) study Active transportation to school over 2 years in relation to weight status and physical activity. Occupational, commuting, and leisure-time physical activity in relation to risk for Type 2 diabetes in middle-aged Finnish men and women The effect of physical activity on breast cancer risk: A cohort study of 30,548 women Low physical activity as a predictor for total and cardiovascular disease mortality in middle-aged men and women in Finland. The association between physical activity in different domains of life and risk of osteoporotic fractures. Physical Activity and Coronary Event Incidence in Northern Ireland and France: The Prospective Epidemiological Study of Myocardial Infarction (PRIME) Walking to Work Is an Independent Predictor of Incidence of Type 2 Diabetes in Japanese Men Low physical activity as a predictor for antihypertensive drug treatment in 25-64-year-old populations in Eastern and south-western Finland Predictors of adoption and maintenance of vigorous physical activity in men and women. Changes in physical activity from walking to school.
abstract: Background and Purpose — The role of physical activity , especially that of occupational and commuting physical activity , in the prediction of stroke risk is not properly established . We assessed the relationship of different types of physical activity with total and type-specific stroke risk . Methods — We prospect ively followed 47 721 Finnish subjects 25 to 64 years of age without a history of coronary heart disease , stroke , or cancer at baseline .  Hazard ratios ( HRs ) for incident stroke were estimated for different levels of leisure time , occupational , and commuting physical activity . Results — During a mean follow-up of 19.0 years , 2863 incident stroke events were ascertained . The multivariate-adjusted ( age , sex , area , study year , body mass index , systolic blood pressure , cholesterol , education , smoking , alcohol consumption , diabetes , and other 2 types of physical activity ) HRs associated with low , moderate , and high leisure time physical activity were 1.00 , 0.86 , and 0.74 ( Ptrend<0.001 ) for total stroke , 1.00 , 0.87 , and 0.46 ( Ptrend=0.011 ) for subarachnoid hemorrhage , 1.00 , 0.77 , and 0.63 ( Ptrend=0.024 ) for intracerebral hemorrhage , and 1.00 , 0.87 , and 0.80 ( Ptrend=0.001 ) for ischemic stroke , respectively . The multivariate-adjusted HRs associated with none , 1 to 29 , and ≥30 minutes of active commuting were 1.00 , 0.92 , and 0.89 ( Ptrend=0.043 ) for total stroke , and 1.00 , 0.93 , and 0.86 ( Ptrend=0.028 ) for ischemic stroke , respectively . Occupational activity had a modest association with ischemic stroke in the multivariate analysis ( Ptrend=0.046 ) . Conclusion — A high level of leisure time physical activity  reduces the risk of all subtypes of stroke . Daily active commuting also reduces the risk of ischemic stroke In the 1970s Archie Cochrane noted that many healthcare procedures and forms of organisation lacked evidence of effectiveness and efficiency , and argued for improved methods of evaluation , moving from clinical opinion and observation to r and omised controlled trials ( RCTs ) . His arguments gradually became accepted in medicine , but there has been considerable resistance among policymakers and research ers to their application to social and public health interventions . This essay argues that opposition to RCTs in public health is often based on a false distinction between healthcare and community setting s , and sometimes on a misunderst and ing of the principles of RCTs in health care . It suggests that just as in medicine , good intentions and received wisdom are not a sufficient basis for making public policy and allocating public funds for social or health improvement Study objective : To determine if a self help intervention , delivered via written interactive material s ( the “ Walk in to Work Out ” pack ) , could increase  active commuting behaviour ( walking and cycling ) . Design : R and omised controlled trial . The intervention group received the “ Walk in to Work Out ” pack , which contained written interactive material s based on the transtheoretical model of behaviour change , local information about distances and routes , and safety information . The control group received the pack six months later . Focus groups were also conducted after six months . Setting : Three workplaces in the city of Glasgow , Scotl and , UK . Participants : 295 employees who had been identified as thinking about , or doing some irregular , walking or cycling to work . Main results : The intervention group was almost twice as likely to increase walking to work as the control group at six months ( odds ratio of 1.93 , 95 % confidence intervals 1.06 to 3.52 ) . The intervention was not successful at increasing cycling . There were no distance travelled to work , gender , or age influences on the results . Twenty five per cent ( 95 % confidence intervals 17 % to 32 % ) of the intervention group , who received the pack at baseline , were regularly actively commuting at the 12 month follow up . Conclusion : The “ Walk in to Work Out ” pack was successful in increasing walking but not cycling . The environment for cycling must be improved before cycling will become a popular option Reports of studies relating physical activity to stroke and cancer sub-types indicate inconsistent findings . Some are hampered by low statistical power , owing to a low number of events , and a failure to adjust for potential confounding variables . The purpose of this study was to relate physical activity to 12 mortality endpoints in a prospect i ve cohort study of 11,663 men aged 40–64 years who responded to an enquiry about travel activity during a baseline medical examination conducted between 1967 and 1969 . During 25 years of follow-up there were 4672  deaths .  Travel activity  was inversely related to mortality attributable to all-causes , coronary heart disease , respiratory disease and lung cancer , whereas the association with stroke was positive . There was evidence for attenuation of some of these associations on adjustment for potentially confounding variables . Our simplistic measure of physical activity may , in part , explain the weak associations seen There is good evidence that physical activity reduces the risk for cardiovascular disease ( 1 - 6 ) , possibly in part by lowering blood pressure ( 7 ) . Although mild or moderate physical activity , such as brisk walking , is a recommended part of the treatment protocol for persons with hypertension ( 8 , 9 ) , it is not known whether mild physical activity , especially walking , reduces the risk for hypertension . With few exceptions , epidemiologic studies of physical activity and hypertension have been cross-sectional rather than prospect i ve . Physical activity was inversely related to blood pressure in cross-sectional and controlled studies ( 7 ) , and in two prospect i ve studies ( 10 , 11 ) , vigorous exercise was inversely related to the subsequent risk for hypertension . Physicians in Japan usually advise their patients to walk to work as often as they can , and indeed , for middle-aged working Japanese men , the journey to and from work seems to be the main source of exercise . We prospect ively examined the relation of mild physical activity , especially walking to work , and leisure-time physical activity to the risk for hypertension during 6 to 16 years of observation . Methods The Osaka Health Survey The Osaka Health Survey is an ongoing cohort study of risk factors for chronic diseases , including hypertension and diabetes . Study participants are male employees of a gas company in Osaka , Japan . Japanese law requires all employers to conduct annual health screenings for all employees . For the purpose s of the Osaka Health Survey , in addition to these annual screenings , all employees 35 years of age or older undergo more detailed biennial clinical examinations and complete question naires on health-related behaviors , including exercise . Study Sample Between 1981 and 1990 , 7979 Japanese men 35 to 63 years of age at entry who had sedentary occupations were enrolled in the study . We excluded 1875 men because they had physician-diagnosed hypertension , borderline hypertension ( systolic blood pressure 140 and < 160 mm Hg , diastolic blood pressure 90 and < 95 mm Hg , or both in men without a history of hypertension ) , diabetes , or impaired glucose tolerance ( fasting plasma glucose level 6.1 mmol/L [ 110 mg/dL ] and < 7.8 mmol/L [ < 140 mg/dL ] in men with no history of diabetes ) at entry . The study sample ultimately consisted of 6104 men . Data Collection and Measurements The biennial clinical examination consisted of a medical history ; a physical examination ; blood pressure measurement ; anthropometric measurements ; measurement of the fasting plasma glucose level ; and surveys of health-related behaviors , such as physical activity , smoking , and daily alcohol consumption . Trained nurses took all measurements . Participants were asked to fast for 12 hours and to avoid smoking and heavy physical activity for more than 2 hours before the examination . After a 5-minute rest in a quiet room , a st and ard mercury sphygmomanometer was used to measure systolic and diastolic blood pressures in the right arm while the participant was seated . Pressure was measured twice , at an interval of a few minutes . Anthropometric measurements included height and body weight , which were measured while the participant was wearing light clothing without shoes . Body mass index was calculated as the weight in kilograms divided by the height in meters squared . The question naire completed by each participant elicited information on leisure-time physical activity , the duration of the walk to work , the nature of the participant 's occupation , and the level of activity involved . Leisure-time physical activity was defined as physical activity unrelated to the participant 's work . Questions about leisure-time physical activity were as follows : Do you engage in any regular physical exercise , such as jogging , bicycling , swimming , and tennis , long enough to work up a sweat ( lasting 30 minutes or more ) ? If yes , how many times per week ? What exercise is this ? The questions about regular physical exercise have been vali date d as a measure of physical exercise ( 12 - 15 ) . In the analysis , participants were classified as engaging in regular physical exercise at least once per week or less than once per week . They were also classified into one of three categories of exercise frequency : 0 ( less than once per week ) , once per week , or two or more times per week . The question about the duration of the walk to work was How long does it take you to walk to this office ? Occupational activity was scored as 1 if the participant 's work was mostly sedentary and 2 if he worked outside or if the job required a lot of lifting and walking . In the present study , we excluded all participants who reported a score of 2 for their occupational activities . Questions about alcohol intake included items about the type of alcoholic beverage , the weekly frequency of alcohol consumption , and the usual amount consumed daily . Alcohol intake was converted to total alcohol consumption ( in milliliters of ethanol per day ) by using st and ard Japanese tables . Current and past smoking habits were classified according to the type and quantity of cigarettes smoked daily . Participants were classified as current smokers , past smokers , or nonsmokers . Hypertension was also diagnosed during the biennial study clinical examinations . All participants underwent medical screening by a physician at least once annually , and hypertension was also diagnosed by the physicians . Hypertension was defined by using World Health Organization criteria as physician-diagnosed hypertension ( systolic blood pressure 160 mm Hg , diastolic blood pressure 95 mm Hg , or both ) or use of antihypertensive medication ( 16 ) . Statistical Analysis Age-adjusted mean values and relevant population characteristics were computed for the duration of the walk to work by using analysis of covariance for continuous variables and the direct method for categorical variables . For each participant , person-years of follow-up were counted from the date at study entry to the date of diagnosis of hypertension or 1 April 1997 , whichever came first . The rate of follow-up was 94 % of the total potential person-years of follow-up . Multivariate Cox proportional-hazards regression models were used to evaluate the simultaneous effects of the duration of the walk to work , the frequency of leisure-time physical activity , age , body mass index  , daily alcohol consumption , smoking status , and fasting plasma glucose level . Baseline systolic and diastolic blood pressure were not included in our primary analyses because they could presumably be in the causal pathway between the exposures ( such as physical activity , age , body mass index , and alcohol consumption ) and risk for hypertension . However , we included systolic and diastolic blood pressure in further models to assess the effect of physical activity on the risk for hypertension independent of their effects on systolic and diastolic blood pressure . The linear trends in risks were evaluated by entering indicators for each categorical level of exposure or by using the median value for each category . As a reference category , we used men with the lowest level of physical activity . To address the potential misclassification of leisure-time physical activity over time , additional analyses were performed on the basis of the data at both study entry ( 1981 to 1990 ) and the examination done 4 years after ( 1985 to 1994 ) each participant was enrolled . We also performed analyses that excluded participants who developed hypertension between study entry ( 1981 to 1990 ) and the third examination done 4 years later ( 1985 to 1994 ) . We calculated the 95 % CI for each relative risk ( 17 ) , and all P values are two-tailed . Statistical analyses were performed by using the SPSS 7.5J software package ( SPSS , Inc. , Chicago , Illinois ) . We estimated the number needed to walk , a value analogous to the number needed to treat . The number needed to treat for a given therapy is the reciprocal of the absolute risk reduction for that treatment ( 18 ) . A 95 % CI for the number needed to treat is obtained simply by taking reciprocals of the values defining the 95 % CI of the absolute risk reduction ( 19 ) . In our study , the number needed to walk was defined as the number of men who would have to adopt walking to avoid a single case of hypertension . The number needed to treat must always be based on an outcome for a specific period of time ( 20 ) ; thus , in estimating the number needed to walk , we chose an observation period of 10 years between study entry ( 1981 to 1986 ) and the examination done 10 years after ( 1991 to 1996 ) each participant was enrolled . Role of the Funding Source The funding agencies did not participate in the collection , analysis , or interpretation of data presented in this report or in the decision to su bmi t the manuscript for publication . Results Of the 6104 men eligible for this study between 1981 and 1990 , we excluded 87 men who did not undergo medical check-ups during the follow-up period . The study sample for analysis consisted of 6017 men . During the 59 784 person-years of follow-up between 1981 and 1997 , 626 men developed hypertension . As the duration of the walk to work increased , body weight and the body mass index decreased ( P for trend=0.037 and 0.035 , respectively ) ( Table 1 ) . We identified no significant relation between the duration of the walk to work and the levels of leisure-time physical activity ( P for trend=0.062 ) . Table 1 . Baseline Characteristics according to Duration of the Walk to Work Duration of the Walk to Work The duration of the walk to work was associated with a decreased risk for incident hypertension ( Table 2 ) . After adjustment for age , body mass index , daily alcohol consumption , smoking status , frequency of leisure-time physical activity , systolic blood pressure , diastolic blood pressure , and fasting plasma glucose level , the relative risk for hypertension was 0.71 ( 95 % CI , 0.52 to 0.97 ) in men whose walk to work lasted 21 minutes or more compared with those BACKGROUND Physical activity is associated with low mortality in men , but little is known about the association in women , different age groups , and everyday activity . OBJECTIVE To evaluate the relationship between levels of physical activity during work , leisure time , cycling to work , and sports participation and all-cause mortality . DESIGN Prospect i ve study to assess different types of physical activity associated with risk of mortality during follow-up after the subsequent examination . Mean follow-up from examination was 14.5 years . SETTING Copenhagen University Hospital , Copenhagen , Denmark . PARTICIPANTS Participants were 13,375 women and 17,265 men , 20 to 93 years of age , who were r and omly selected .  Physical activity was assessed by self-report , and health status , including  blood pressure , total cholesterol level , triglyceride levels , body mass index , smoking , and educational level  , was evaluated . MAIN OUTCOME MEASURE All-cause mortality . RESULTS A total of 2,881 women and 5,668 men died . Compared with the sedentary , age- and sex-adjusted mortality rates in leisure time physical activity groups 2 to 4 were 0.68 ( 95 % confidence interval , 0.64 - 0.71 ) , 0.61 ( 95 % confidence interval , 0.57 - 0.66 ) , and 0.53 ( 95 % confidence interval , 0.41 - 0.68 ) , respectively , with no difference between sexes and age groups . Within the moderately and highly active persons , sports participants experienced only half the mortality of non participants . Bicycling to work decreased risk of mortality in approximately 40 % after multivariate adjustment , including leisure time physical activity . CONCLUSIONS Leisure time physical activity was inversely associated with  all-cause mortality in both men and women in all age groups . Benefit was found from moderate leisure time physical activity , with further benefit from sports activity and bicycling as transportation Background Walking and cycling to school are one source of regular physical activity . The aim of this two years observational study in pre-pubertal children was to evaluate if walking and cycling to school was associated with higher total amount of physical activity and larger gain in bone mineral content ( BMC ) and bone width than when going by car or bus . Methods 133 boys and 99 girls aged 7 - 9 years were recruited to the Malmö Prospect i ve Paediatric Osteoporosis Prevention ( POP ) study .  BMC ( g ) was measured by dual X-ray absorptiometry ( DXA ) in total body , lumbar spine ( L2-L4 ) and femoral neck ( FN ) at baseline and after 24 months . Bone width was measured in L2-L4 and FN . Skeletal changes in the 57 boys and 48 girls who consistently walked or cycled to school were compared with the 24 boys and 17 girls who consistently went by bus or car . All children remained in Tanner stage I. Level of everyday physical activity was estimated by accelerometers worn for four consecutive days and question naires . Comparisons were made by independent student 's t-tests between means and Fisher 's exact tests . Analysis of covariance ( ANCOVA ) was used to adjust for group differences in age at baseline , duration of organized physical activity , annual changes in length and BMC or bone width if there were differences in these traits at baseline . Results After the adjustments , there were no differences in the annual changes in BMC or bone width when comparing girls or boys who walked or cycled to school with those who went by car or bus . Furthermore , there were no differences in the levels of everyday physical activity objective ly measured by accelerometers and all children reached above the by the United Kingdom Expert Consensus Group recommended level of 60 minutes moderate to vigorous physical activity per day . Conclusion A physical active transportation to school for two years is in pre-pubertal children not associated with a higher accrual of BMC or bone width than a passive mode of transportation , possibly due to the fact that the everyday physical activity in these pre-pubertal children , independent of the mode of school transportation , was high OBJECTIVE To prospect ively examine potential benefits of active commuting to school on measures of weight status and physical activity in a sample of youth . RESEARCH METHODS AND PROCEDURES A cohort of students from seven elementary schools was measured four times -- in the fall and spring of fourth grade ( N = 1083 ) and fifth grade ( N = 924 ) . Participants were classified as active ( walking , biking , or skateboarding to school almost every day for baseline analyses or at least 2 d/wk for analyses of consistent active commuting ) or non-active commuters to school . Accelerometers were used to measure physical activity . Height , weight , and skinfolds were objective ly assessed . RESULTS Boys who actively commuted to school had lower BMI ( p < 0.01 ) and skinfolds ( p < 0.05 ) than non-active commuters to school in the fourth grade . Active commuting to school over 2 years was not associated with BMI change or overweight status . DISCUSSION Walking and cycling to school may contribute to preventing excessive weight gain , or leaner children may walk or cycle to school Aim /hypothesisLeisure-time physical activity can reduce the risk of Type 2 diabetes , but the potential effect of different types of physical activity is still uncertain . This study is to examine the relationship of occupational , commuting and leisure-time physical activity with the incidence of Type 2 diabetes . Methods We prospect ively followed 6898 Finnish men and 7392 women of 35 to 64 years of age without a history of stroke , coronary heart disease , or diabetes at baseline . Hazards ratios of incidence of Type 2 diabetes were estimated by levels of occupational , commuting , and leisure-time physical activity . Results During a mean follow-up of 12 years , there were 373 incident cases of Type 2 diabetes . In both men and women combined , the hazards ratios of diabetes associated with light , moderate and active work were 1.00 , 0.70 and 0.74 ( p=0.020 for trend ) after adjustment for confounding factors ( age , study year , sex , systolic blood pressure , smoking , education , the two other types of physical activity and BMI ) . The multivariate-adjusted hazards ratios of diabetes with none , 1 to 29 , and more than 30 min of walking or cycling to and from work were 1.00 , 0.96 , and 0.64 ( p=0.048 for trend ) . The multivariate-adjusted hazards ratios of diabetes for low , moderate , high levels of leisure-time physical activity were 1.00 , 0.67 , and 0.61 ( p=0.001 for trend ) ; after additional adjustment for BMI , the hazards ratio was no longer significant . Conclusions /interpretationModerate and high occupational , commuting or leisure-time physical activity independently and significantly reduces risk of Type 2 diabetes among the middle-aged general population Background : In epidemiological studies abundant physical activity has been related to decreased  breast cancer  risk , though the results have been inconsistent . The purpose of this paper was to study the association of physical activity at leisure and commuting to work and incidence of breast cancer . Methods : The study cohort consisted of 30,548 female participants of the Finnish adult health behaviour survey , based on annual r and om sample s of Finns aged 15–64 , collected in 1978–1993 . By the end of 1995 , 332 breast cancer cases had been diagnosed in the cohort . Relative risks of breast cancer were adjusted for age at survey , body mass index ( BMI ) , education , length of follow-up , parity and age at first birth using Poisson regression models . Results : Compared to women exercising less than once a week , the adjusted relative risk of breast cancer for women exercising once a week was 0.80 ( 95 % confidence interval ( CI ) : 0.58–1.10 ) , for women exercising 2–3 times per week 0.92 ( 95 % CI : 0.78–1.22 ) and for women exercising daily 1.01 ( 95 % CI : 0.72–1.42 ) . Women who reported commuting , walking or bicycling to work 30 min or more daily had slightly lower adjusted risk of breast cancer ( RR : 0.87 , 95 % CI : 0.62–1.24 ) than women working at home , being unemployed or driving a car to working place . Conclusion : Although a small protective effect of regular physical activity for breast cancer incidence was found in physical activity when commuting to work , the role of the physical activity in breast cancer prevention is still an open question AIMS To investigate separately for men and women whether moderate or high leisure time physical activity , occupational physical activity , and commuting activity are associated with a reduced cardiovascular disease ( CVD ) and all-cause mortality , independent of CVD risk factors and other forms of physical activity . METHODS AND RESULTS Prospect i ve follow-up of 15,853 men and 16,824 women aged 30 - 59 years living in eastern and south-western Finl and ( median follow-up time 20 years ) .  CVD and all-cause mortality were lower ( 9 - 21 % ) in men and women ( 2 - 17 % ) who were moderately or highly physically active during leisure time . Moderate and high levels of occupational physical activity decreased CVD and all-cause mortality by 21 - 27 % in both sexes . Women spending daily 15 min or more in walking or cycling to and from work had a reduced CVD and all-cause mortality before adjustment for occupational and leisure time physical activity . Commuting activity was not associated with CVD or all-cause mortality in men . CONCLUSION Moderate and high levels of leisure time and occupational physical activity are associated with a reduced CVD and all-cause mortality among both sexes . Promoting already moderate levels of leisure time and occupational physical activity are essential to prevent premature CVD and all-cause mortality A large body of epidemiological evidence suggests an inverse relationship between  physical activity  and risk of fractures . However , it is unclear how this association varies according to the domain of life in which the activity is undertaken . In this analysis of the European Prospect i ve Investigation of Cancer-Norfolk study , we assessed total and domain-specific physical activity  using a vali date d question naire ( EPAQ2 ) in 14,903 participants ( 6514 men , mean age 62 year ) who also underwent quantitative ultrasound of the heel .  After a median follow-up of 7.5 years , there were 504 fractures of which 164 were hip fractures . In multivariable linear regression analysis , broadb and ultrasound attenuation ( BUA ) was positively associated with total and leisure-time activities while showing no association with transportation and work activities . Home activities were associated with a lower BUA  among younger participants . In multivariable Cox proportional-hazards models , moderate activities at home and in leisure time were associated with lower hip fracture risk among women ( hazard ratios [ HR ] 0.51 and 0.55 , p value 0.02 and 0.03 , respectively ) . Among men , leisure-time activities were associated with lower risk of hip fracture ( HR=0.58 ; p for trend<0.001 ) whereas activities at home were associated with higher risk of any fracture ( HR=1.25 ; p for trend=0.008 ) . Walking for leisure or transport was associated with lower risk of fracture in both men and women . Multivariable fractional polynomial modelling showed a U-shaped association between home activities and fracture risk especially among women . This study suggests that different domains of physical activity may relate differently to fracture risk and these relationships may vary by sex Background —The influence of physical activity on the incidence of angina pectoris and hard coronary events ( myocardial infa rct ion and coronary deaths ) was examined in Northern Irel and and France at contrasting risk for coronary heart disease ( CHD ) and with different physical activity patterns . Methods and Results — Participants of the Prospect i ve Epidemiological Study of Myocardial Infa rct ion ( PRIME ) ( n=9758 ; age , 50 to 59 years ) , free of CHD at baseline , were followed up for 5 years : 167 hard CHD and 154 angina events were recorded .  Net energy expenditure ( EE ) as the result of physical activity was assessed by means of the MONICA Optional Study of Physical Activity Question naire ( MOSPA-Q ) .  Leisure-time physical activity EE was calculated ; subjects were also categorized as to whether they performed high-intensity leisure-time activities or walked or cycled to work . After multivariate adjustment , leisure-time physical activity EE was associated with a lower risk of hard CHD events ( P < 0.04 ) , whereas walking or cycling to work was not independently related to hard CHD events . No interaction by country was found . The beneficial effect of leisure-time physical activity  was also present among subjects who did not report high-intensity activities ( P < 0.04 ) , with similar results in France and Northern Irel and . In contrast , an increasing level of leisure-time physical activity  was associated with a higher risk of angina in both countries . Conclusions —These data indicate a beneficial effect of leisure-time physical activity EE on hard CHD incidence in middle-aged men , which could partly explain the unfavorable rate of CHD in Northern Irel and . The higher level of leisure-time activities in France could , in part , explain its lower rate of CHD Previous epidemiological studies have shown that vigorous physical activity reduces the development of type 2 diabetes ( 1–3 ) . A recommendation from the Centers for Disease Control and Prevention reported that individuals should engage in ≥30 min of moderate-intensity physical activity , such as brisk walking , on most days of the week for health promotion and disease prevention ( 4 ) ; however , it is unclear whether mild physical activity ( i.e. , walking to walk ) reduces the risk for type 2 diabetes . In the present study , we examined the relationship between walking to work  and the development of type 2 diabetes during a 4-year observational period . The Kansai Healthcare Study is an ongoing cohort investigation design ed to clarify the risk factors for cardiometabolic diseases . Between April 2000 and March 2001 , 12,647 male employees of a company in the area of Kansai , Japan , who were aged 40–55 years at entry and considered to be involved in sedentary jobs were enrolled in this study . All employees aged ≥40 years underwent annual detailed medical check-ups . The protocol for this research was review ed by the Human Subjects Review Committee at Osaka City University . For current analysis , study participants consisted of 11,073 Japanese men aged 40–55 years at entry with a fasting plasma glucose ( FPG ) < 126 mg/dl and not taking oral hypoglycemic medication or insulin . A 4-year follow-up examination after baseline was conducted between April 2004 and March 2005 . We excluded 53 men because of death and 2,016 men because of Objective To determine whether low leisure-time physical activity , occupational physical activity and commuting activity independently increase the risk of hypertension when adjusted for most risk factors for hypertension and for different forms of physical activity . Design Population -based prospect i ve cohort study . Setting Eastern and south-western Finl and . Participants Men ( n = 5935 ) and women ( n = 6227 ) aged 25 - 64 years . Main outcome measure Initiation of free-of-charge medication for hypertension during a mean follow-up time of 11.3 years . Results Men with high  leisure-time physical activity had a reduced risk of hypertension when adjustment had been made for age , area and year of survey , education , smoking , alcohol intake , baseline systolic blood pressure ( SBP ) , body mass index ( BMI ) , commuting activity and occupational physical activity [ hazard ratio ( HR ) 0.79 ; 95 % confidence interval ( CI ) 0.63 to 0.99 ] . Women with high leisure-time physical activity had a reduced risk of hypertension when adjusted for age , area and time of survey ( HR 0.65 ; 95 % CI 0.46 to 0.91 ) . This association was no longer significant when further adjustments were made for other covariates ( HR 0.73 ; 95 % CI 0.52 to 1.03 ) . High  occupational physical activity  reduced the risk of hypertension only among men and women combined when adjustment was made for age , area and time of survey , education , smoking and alcohol intake , in addition to baseline SBP , BMI , commuting activity and leisure-time physical activity ( HR 0.83 ; 95 % CI 0.72 to 0.96 ) . Commuting activity was not associated with risk of hypertension in multivariate models . Conclusion High levels of leisure-time physical activity are associated with a reduced risk of hypertension , independently of most common risk factors for hypertension , occupational physical activity and commuting activity . Promoting leisure-time physical activity is essential to prevent hypertension BACKGROUND This study examined predictors of adoption and maintenance of vigorous physical activity over time in a sample of 1,719 r and omly selected women and men . METHODS Based on reported frequency of vigorous exercise in a mail survey at baseline , subjects were classified as sedentary ( zero sessions per week ) , intermediate ( one to two sessions per week ) , or active ( three or more sessions per week ) . RESULTS On the same survey subjects reported on 25 potential determinants of physical activity based on a comprehensive learning model . Twenty-four months later , 85 % of subjects were resurveyed , and their physical activity levels were classified . Within each baseline category and gender subgroup , predictors of follow-up physical activity were identified . In multivariate analyses , adoption of  vigorous exercise by sedentary men was predicted by self-efficacy , age ( inverse ) , and neighborhood environment ( inverse ) . Adoption by sedentary women was predicted by education , self-efficacy , and friend and family support for exercise . Maintenance of vigorous physical activity  was predicted by self-efficacy and age ( inverse ) for initially active men and by education for initially active women . CONCLUSION These results suggest that factors influencing adoption are different for men and women , and there may be different factors influencing adoption versus maintenance of vigorous physical activity Active commuting to school ( e.g. walking or bicycling ) has been suggested as a strategy to increase  children ’s physical activity 1 , 2 and a number of walk-to-school websites now exist . 3–5 Several observational studies have found positive associations between walking to school and physical activity 6–9 but they are unable to determine the causal direction . Adult-chaperoned walks to school ( i.e. , walking school bus1 , 5 ) have been evaluated 10–12 but no research was found that assessed objective ly measured changes in physical activity from walking to school . Walk-to-school programs can be a component of comprehensive school health plans , have particular relevance for school nurse/health staff and physical education faculty and can be adapted to suit the schools ’ physical and social environment . Therefore , we completed a small , short-term pilot and feasibility r and omized control trial to 1 ) test the feasibility of the walking school bus as an intervention strategy and 2 ) to identify any changes in physical activity from walking to school . A r and omized controlled trial design was used with all participants completing one week of baseline automobile commuting . Students were then r and omized , for the second week , to either a control group that continued to be driven to school or an intervention group that participated in the walking school bus .  Families were recruited from one elementary school ( Menlo Park , CA ) . Eighteen families responded and met the inclusion criteria : 1 ) student in 3rd–5th grade and 2 ) currently being driven to school at least four days/week . Six families declined to participate , due to time constraints ( n=4 ) , shared custody ( n=1 ) , and general concern ( n=1 ) . Therefore , 12 students were r and omized to a control ( CON  , n=6 ) or intervention ( WALK  , n=6 ) group . All students completed the study protocol as design ed . One student in the WALK group was excluded from analysis due to activity monitor malfunction , leaving five WALK and six CON students in the analysis sample . This study was approved by the Stanford University Administrative Panel on Human Subjects in Medical Research . This study was conducted during March and April of 2005 . The ActiGraph  physical activity monitor was used to measure physical activity . 13–15 One-minute data collection time intervals ( epochs ) were used for this study . An elastic belt with an attached monitor was fit to each student on the first day of the study ( always a weekend ) . Students were instructed to wear the monitor at all times for 14 consecutive days except when swimming , bathing , or sleeping . All students were instructed to maintain their normal activities during the baseline week . On the fifth day , families were notified of their group r and omization and , for the WALK group , the planned route and schedule . The morning commute for the CON group was not altered . A walking school bus , led by one study personnel , followed the safest route to school based on the location of the students ’ homes relative to each other and the school . Students walked at their normal pace but were encouraged to stay together as a group . A wagon , pulled by the study personnel , was used to transport backpacks and instruments . If a student lived more than 1.6 Km from the school , the parent/guardian dropped the student off at one of the other student ’s homes ( 1.1 Km from school ) and he/she walked the remainder of the trip . Raw accelerometer data were reduced to summary variables using a custom software program . 9 For analysis , accelerometer data were summarized for the total week and weekdays . Each weekday was also divided into four time blocks ; before- , during- , and after-school and evening . Average monitor counts·min−1 and the average percent of time spent in moderate-tovigorous physical activity ( % MVPA ) were calculated for each student using age-specific count cutoffs 16 and change scores ( intervention – baseline ) calculated . Between group comparisons used non-parametric Wilcoxon Rank Sum tests with a two-tailed alpha=0.05 . CON ( n=6 ) and WALK ( n=5 ) students were ( mean±SD ) 9.5±1.02 and 9.7±0.90 years old . The CON group had four boys ( all Caucasian ) and two girls ( 1 Caucasian , 1 Chinese ) . The WALK group had two boys and three girls ( all Caucasian ) . On average , CON and WALK students lived 1.3±0.68 and 0.9±0.46 Km from school . The time required to walk to school for the WALK students ranged from 10–36 minutes and was proportional to the distance traveled 0.4–1.1 Km ( mean , 0.8 Km ) ( Spearman r=0.95 ) . Compared to students in the CON group , WALK students significantly increased their counts·min-1 and % MVPA ( p≤0.02 ) before school ( Table 1 ) . This difference was even more pronounced when only looking at the General Commute Time ( GCT ) , defined as the 45 minutes before school ( p<0.01 ) . While there was no change for the CON group ( 12 min of MVPA ) , the WALK group added , on average , 14 minutes of MVPA during the GCT ( between group p=0.05 ) . No significant differences were detected for the other weekday periods . No significant between group differences were detected ( all p≥0.40 ) for the change in counts·min−1 or % MVPA averaged over all useable days or weekdays . Table 1 Average counts·min-1 and percent of time spent in MVPA by group by weekday time blocks , all days , and weekdays To our knowledge , this is the first experimental study to investigate the effect of walking to school on physical activity . The walking school bus did prove feasible in this small sample . Compared to students that were driven to school , those that walked to school increased their MVPA during the GCT by 14 minutes per day . Qualitative data collected at the end of the intervention indicated that the walking school bus was well liked . Parents noted that it was a , “ less stressful start to the day ” and another mentioned , “ She can do it ! And she enjoys walking . She even wanted to walk home ” . Students indicated that they enjoyed walking with others and one student noted that he , “ Did n't feel as tired in the morning compared to when I am driven to school ” . Two students indicated they did not like getting up earlier and none of the students liked the “ loud , embarrassing wagon ” . Five of the six students in the WALK group said they would continue to walk to school . In this experimental study we found no significant group differences for total daily or weekday physical activity or percent of time spent in MVPA . This was likely due to insufficient power to detect such differences , given the high variability of physical activity behavior and measurement error . The 14 minute increase in MVPA during the general commute time for the WALK students represents approximately 25 % of the recommended 60-minutes of MVPA per day . The promising results of this small experimental study justify larger walk to school experiments to examine whether walk to school interventions can impact total daily physical activity and MVPA , as well as other health and behavior outcomes . Additional community level benefits include less car congestion and emissions and improved neighborhood safety via more frequent social interactions with neighbors and greater community cohesion . Since walking to school will likely take longer than being driven , the morning routine may change to accommo date this . The child may need to get up earlier , potentially reducing the amount of time for sleeping and eating breakfast . Therefore , quality and quantity of sleep , consumption of breakfast and overall dietary behavior of students that walk to school should be considered . Lastly , such school- and community-based efforts should seek to engage school personnel and parent and community volunteers as walking school bus chaperones.17 The experiences from such programs can be incorporated into physical education and science curriculums as experiential learning opportunities ( e.g. , walkability audits ; car , bike , and pedestrian counts ; step or distance goals for active commuting , etc … )
target: Active travel may have positive effects on health outcomes , but there is little robust evidence to date of the effectiveness of active transport interventions for reducing obesity .
background: BACKGROUND Increasing active travel ( primarily walking and cycling ) has been widely advocated for reducing obesity levels and achieving other population health benefits .
  However , the strength of evidence underpinning this strategy is unclear .
  This study aim ed to assess the evidence that active travel has significant health benefits .