Obesity and physical inactivity are related to impaired physical health of breast cancer survivors. Physical inactivity and short-term all-cause mortality in adults with chronic disease. The economic burden of physical inactivity in Canada. Prevalence of physical inactivity in nine rural INDEPTH Health and Demographic Surveillance Systems in five Asian countries Fatness leads to inactivity, but inactivity does not lead to fatness: a longitudinal study in children (EarlyBird 45) Physical activity and cause-specific mortality in men: Further evidence from the Whitehall study Body mass index, physical inactivity and low level of physical fitness as determinants of all-cause and cardiovascular disease mortality—16 y follow-up of middle-aged and elderly men and women Physical activity trajectories and mortality: population based cohort study The effect of physical activity on mortality and cardiovascular disease in 130 000 people from 17 high-income, middle-income, and low-income countries: the PURE study The effects of physical activity and body mass index on cardiovascular, cancer and all-cause mortality among 47 212 middle-aged Finnish men and women Combined effects of obesity and physical activity in predicting mortality among men. Physical activity and obesity mediate the association between childhood motor function and adolescents’ academic achievement A school-based intervention to reduce overweight and inactivity in children aged 6–12 years: study design of a randomized controlled trial Physical Activity Level and Colorectal Cancer Mortality Overweight, obesity, and mortality from cancer in a prospectively studied cohort of U.S. adults. Associations between Physical Activity and Health Parameters in Adolescent Pupils in Egypt A school-based physical activity program to improve health and fitness in children aged 6–13 years ("Kinder-Sportstudie KISS"): study design of a randomized controlled trial [ISRCTN15360785]
AIM The aim of the present study was to examine the impact of obesity and physical activity on the health and wellbeing of patients with breast cancer shortly after the adjuvant treatments . PATIENTS AND METHODS A total of 537 women aged 35 to 68 years with newly-diagnosed breast cancer were enrolled into the exercise intervention study .  The physical activity , physical performance ( 2-km walking test ) , cardiovascular risk factors , quality of life ( EORTC-QoL-C30 ) , co-morbidities and body-mass index ( BMI ) were measured after the adjuvant treatments . RESULTS Overall , 191 ( 39 % ) patients were overweight ( BMI = 25 - 30 ) and 85 ( 17 % ) obese ( BMI ≥ 30 ) . Physical activity and performance ( p<0.001 and p<0.001 ) , QoL ( p<0.001 ) and high density lipoprotein (HDL)-cholesterol decreased ( p<0.001 ) whereas age ( p=0.009 ) , co-morbidities ( p<0.001 ) , hypertension ( p=0.011 ) , metabolic syndrome ( p<0.001 ) , low density lipoprotein (LDL)-cholesterol ( p=0.0043 ) , triglycerides ( p<0.001 ) , glucose ( p<0.001 ) and insulin ( p<0.001 ) increased linearly with BMI . Higher waist circumference ( p=0.0011 ) , triglyceride ( p=0.020 ) , insulin ( p=0.0098 ) , rate of metabolic syndrome ( p=0.028 ) , and lower HDL-cholesterol ( p=0.012 ) and QoL ( p<0.001 ) were associated with low physical activity . Physical activity and BMI were the most important determinants of physical performance ( p<0.001 and p<0.001 , respectively ) . CONCLUSION Obesity and a sedentary lifestyle are related to poor physical performance , increased risk of cardiovascular diseases and impaired QoL , leading to a vicious circle , which impairs patients ' physical health and OBJECTIVE To ascertain the relationship of physical inactivity and short-term all-cause mortality in a prospect i ve cohort of r and omly selected managed care organization members aged 40 years and older who have multiple chronic diseases . METHODS Clinical data bases were used to identify all health plan members aged 40 years and older with 2 or more chronic health conditions ( hypertension , coronary heart disease , diabetes mellitus , or dyslipemia ) in 1994 . A r and om sample of 2336 members was surveyed by mail and telephone interview regarding their health-related behaviors .  Survey data were linked to mortality data from the 1995 to 1997 Minnesota Death Index . Cox proportional hazards regression was used to ascertain the association between physical inactivity and subsequent all-cause mortality , adjusting for potential confounders . RESULTS Members who reported less than 30 minutes a week of physical activity at baseline had a subsequent mortality risk ratio of 2.82 ( P<.001 ) vs those with 30 or more minutes of physical activity a week . Increased mortality risk persisted ( mortality risk ratio , 2.15 ; P<.001 ) after adjustments for age , sex , current smoking , functional impairment , and comorbidity score . CONCLUSIONS In adults with chronic diseases , the physically inactive had higher observed mortality within a 42-month period . If physical inactivity reflects an independent mortality risk , efforts to maintain physical activity in such patients may yield significant clinical benefits within a short period . By contrast , if inactivity is primarily a proxy for other factors that elevate mortality risks , a simple physician inquiry regarding inactivity may help to identify patients at risk of death BACKGROUND About two-thirds of Canadians are physically inactive . As a risk factor for several chronic diseases , physical inactivity can potentially be a substantial public health burden . We estimated the direct health care costs attributable to  physical inactivity  in Canada , the number of lives lost prematurely each year that are attributable to a sedentary lifestyle and the effect that a reduction of 10 % in inactivity levels ( a Canadian objective for 2003 ) could have on reducing direct health care costs . METHODS We calculated summary relative risk ( RR ) estimates from prospect i ve longitudinal studies of the effects of physical inactivity on coronary artery disease , stroke , colon cancer , breast cancer , type 2 diabetes mellitus and osteoporosis . We then computed the population -attributable fraction ( PAF ) for each illness from the summary RR and the prevalence of physical inactivity ( i.e. , 62 % ) and applied the PAF to the total direct health care expenditures for 1999 and to the number of deaths in 1995 associated with each disease to determine the health care costs and lives lost prematurely that were directly attributable to physical inactivity . RESULTS About $ 2.1 billion , or 2.5 % of the total direct health care costs in Canada , were attributable to physical inactivity in 1999 . A sensitivity analysis ( simultaneously varying each of the health care costs and PAF by + /- 20 % ) indicated that the costs could be as low as $ 1.4 billion and as high as $ 3.1 billion . About 21,000 lives were lost prematurely in 1995 because of inactivity . A 10 % reduction in the prevalence of physical inactivity has the potential to reduce direct health care expenditures by $ 150 million a year . INTERPRETATION Physical inactivity represents an important public health burden in Canada . Even modest reductions in inactivity levels could result in substantial cost savings Background : Physical inactivity leads to higher morbidity and mortality from chronic non-communicable diseases ( NCDs ) such as stroke and heart disease . In high income countries , studies have measured the population level of physical activity , but comparable data are lacking from most low and middle-income countries . Objective : To assess the level of physical inactivity  and its associated factors in selected rural sites in five Asian countries . Methods : The multi-site cross-sectional study was conducted in nine rural Health and Demographic Surveillance System ( HDSS ) sites within the INDEPTH Network in Bangladesh , India , Indonesia , Thail and , and Vietnam . Using the methodology from the WHO STEPwise approach to Surveillance ( STEPS ) , about 2,000 men and women aged 25–64 years were selected r and omly from each HDSS sampling frame .  Physical activity at work and during leisure time , and on travel to and from places , was measured using the Global Physical Activity Question naire version 2 ( GPAQ2 ) . The total activity was calculated as the sum of the time spent in each domain of activities in metabolic equivalent-minutes per week , and was used to determine the level of physical activity . Multivariable logistic regression was used to assess demographic factors associated with a low level of physical activity . Results : The prevalence of physical inactivity ranged from 13 % in Chililab HDSS in Vietnam to 58 % in Filabavi HDSS in Vietnam . The majority of men  were physically active , except in the two sites in Vietnam . Most of the respondents walked or cycled for at least 10 minutes to get from place to place , with some exceptions in the HDSSs in Indonesia and Thail and . The majority of respondents , both men and women , were inactive during their leisure time . Women , older age , and high level of education were significantly associated with physical inactivity . Conclusion : This study showed that over 1/4 men and 1/3 women in Asian HDSSs within the INDEPTH Network are physically inactive . The wide fluctuations between the two HDSS in Vietnam offer an opportunity to explore further urbanisation and environmental impacts on physical activity . Considering the importance of physical activity in improving health and preventing chronic NCDs , efforts need to be made to promote physical activity particularly among women , older people , and high education groups in these setting Objective To establish in children whether inactivity is the cause of fatness or fatness the cause of inactivity . Design A non-intervention prospect i ve cohort study examining children annually from 7 to 10 years . Baseline versus change to follow-up associations were used to examine the direction of causality . Setting Plymouth , Engl and . Participants 202 children ( 53 % boys , 25 % overweight/obese ) recruited from 40 Plymouth primary schools as part of the EarlyBird study . Main outcome measures  Physical activity ( PA ) was measured using Actigraph accelerometers . The children wore the accelerometers for 7 consecutive days at each annual time point . Two components of PA were analysed : the total volume of PA and the time spent at moderate and vigorous intensities . Body fat per cent ( BF% ) was measured annually by dual energy x ray absorptiometry . Results BF% was predictive of changes in PA  over the following 3 years , but PA levels were not predictive of subsequent changes in BF% over the same follow-up period . Accordingly , a 10 % higher BF% at age 7 years predicted a relative decrease in daily moderate and vigorous intensities of 4 min from age 7 to 10 years ( r=−0.17 , p=0.02 ) , yet more PA at 7 years did not predict a relative decrease in BF% between 7 and 10 years ( r=−0.01 , p=0.8 ) . Conclusions Physical inactivity appears to be the result of fatness rather than its cause . This reverse causality may explain why attempts to tackle childhood obesity by promoting PA have been largely unsuccessful 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 OBJECTIVE : To investigate the independent associations and the possible interaction of  body mass index ( BMI ) , leisure time physical activity ( LTPA ) and perceived physical fitness and functional capability with the risk of mortality . DESIGN : Prospect i ve 16 y follow-up study .SUBJECTS : A regionally representative cohort of 35–63 -y-old Finnish men ( n=1090 ) and women ( n=1122 ) . MEASUREMENTS : All-cause , cardiovascular disease ( CVD ) and coronary heart disease ( CHD ) mortality were derived from the national census data until the end of September 1996 while the initial levels of BMI , LTPA , physical fitness and function were determined from self-administered question naires . RESULTS : After adjustment for age , marital and employment status , perceived health status , smoking and alcohol consumption , the Cox proportional hazards model showed that BMI was not associated with the risk of death among the men or the women . Compared with the most active subjects the men and women with no weekly vigorous activity had relative risks of 1.61 ( 95 % confidence interval , CI , 0.98–2.64 ) and 4.68 ( 95 % CI , 1.41–15.57 ) , respectively , for CVD mortality , and for the men there was a relative risk of 1.66 ( 95 % CI , 0.92–2.99 ) for CHD mortality . When compared with the men who perceived their fitness as better than their age-mates , the men with the ‘ worse ’ assessment had a relative risk of 3.29 ( 95 % CI , 1.80–6.02 ) for all-cause mortality and 4.37 ( 95 % CI , 1.80–10.6 ) for CVD mortality . Men with at least some difficulty in walking a distance of 2 km had a relative risk of 1.62 ( 95 % CI , 1.05–2.50 ) for all-cause mortality when compared with those who had no functional difficulties . In addition , in the comparison with subjects with no functional difficulties , the men and women who had some difficulty climbing several flights of stairs had relative risks of 1.47 ( 95 % CI , 0.97–2.23 ) and 2.39 ( 95 % CI , 1.25–4.60 ) for all-cause mortality , respectively . For CVD mortality the relative risks were 1.85 ( 95 % CI , 1.04–3.30 ) and 3.38 ( 1.22–9.41 ) , respectively . CONCLUSIONS : Although BMI did not prove to be an independent risk factor for mortality from CVD , CHD or from all causes combined , perceived physical fitness and functional capability did . An increase in LTPA seems to have a similar beneficial effect on the mortality risk of obese and nonobese men and women , and the effect also seems to be similar for fit and unfit subjects Abstract Objective To assess the prospect i ve associations of baseline and long term trajectories of physical activity on mortality from all causes , cardiovascular disease , and cancer . Design Population based cohort study . Setting Adults from the general population in the UK . Participants 14 599 men and women ( aged 40 to 79 ) from the European Prospect i ve Investigation into Cancer and Nutrition-Norfolk cohort , assessed at baseline ( 1993 to 1997 ) up to 2004 for lifestyle and other risk factors ; then followed to 2016 for mortality ( median of 12.5 years of follow-up , after the last exposure assessment ) . Main exposure  Physical activity energy expenditure ( PAEE ) derived from question naires , calibrated against combined movement and heart rate monitoring . Main outcome measures Mortality from all causes , cardiovascular disease , and cancer . Multivariable proportional hazards regression models were adjusted for age , sex , sociodemographics , and changes in medical history , overall diet quality , body mass index , blood pressure , triglycerides , and cholesterol levels . Results During 171 277 person years of follow-up , 3148 deaths occurred . Long term increases in PAEE were inversely associated with mortality , independent of baseline PAEE . For each 1 kJ/kg/day per year increase in PAEE ( equivalent to a trajectory of being inactive at baseline and gradually , over five years , meeting the World Health Organization minimum physical activity guidelines of 150 minutes/week of moderate-intensity physical activity ) , hazard ratios were : 0.76 ( 95 % confidence interval 0.71 to 0.82 ) for all cause mortality , 0.71 ( 0.62 to 0.82 ) for cardiovascular disease mortality , and 0.89 ( 0.79 to 0.99 ) for cancer mortality , adjusted for baseline PAEE , and established risk factors . Similar results were observed when analyses were stratified by medical history of cardiovascular disease and cancer . Joint analyses with baseline and trajectories of physical activity show that , compared with consistently inactive individuals , those with increasing physical activity trajectories over time experienced lower risks of mortality from all causes , with hazard ratios of 0.76 ( 0.65 to 0.88 ) , 0.62 ( 0.53 to 0.72 ) , and 0.58 ( 0.43 to 0.78 ) at low , medium , and high baseline physical activity , respectively . At the population level , meeting and maintaining at least the minimum physical activity recommendations would potentially prevent 46 % of deaths associated with physical inactivity . Conclusions Middle aged and older adults , including those with cardiovascular disease and cancer , can gain substantial longevity benefits by becoming more physically active , irrespective of past physical activity levels and established risk factors . Considerable population health impacts can be attained with consistent engagement in physical activity during mid to late life BACKGROUND Physical activity has a protective effect against  cardiovascular disease ( CVD )  in high-income countries , where physical activity is mainly recreational , but it is not known if this is also observed in lower-income countries , where physical activity is mainly non-recreational . We examined whether different amounts and types of physical activity are associated with lower mortality and CVD  in countries at different economic levels . METHODS In this prospect i ve cohort study , we recruited participants from 17 countries ( Canada , Sweden , United Arab Emirates , Argentina , Brazil , Chile , Pol and , Turkey , Malaysia , South Africa , China , Colombia , Iran , Bangladesh , India , Pakistan , and Zimbabwe ) . Within each country , urban and rural areas in and around selected cities and towns were identified to reflect the geographical diversity . Within these communities , we invited individuals aged between 35 and 70 years who intended to live at their current address for at least another 4 years .  Total physical activity  was assessed using the  International Physical Activity Question naire ( IPQA ) . Participants with pre-existing CVD were excluded from the analyses . Mortality and CVD were recorded during a mean of 6·9 years of follow-up . Primary clinical outcomes during follow-up were mortality plus major CVD ( CVD mortality , incident myocardial infa rct ion , stroke , or heart failure ) , either as a composite or separately . The effects of physical activity on mortality and CVD were adjusted for sociodemographic factors and other risk factors taking into account household , community , and country clustering . FINDINGS Between Jan 1 , 2003 , and Dec 31 , 2010 , 168 916 participants were enrolled , of whom 141 945 completed the IPAQ . Analyses were limited to the 130 843 participants without pre-existing CVD . Compared with low physical activity ( < 600 metabolic equivalents [ MET ] × minutes per week or < 150 minutes per week of moderate intensity physical activity ) , moderate ( 600 - 3000 MET × minutes or 150 - 750 minutes per week ) and high physical activity ( > 3000 MET × minutes or > 750 minutes per week ) were associated with grade d reduction in mortality ( hazard ratio 0·80 , 95 % CI 0·74 - 0·87 and 0·65 , 0·60 - 0·71 ; p<0·0001 for trend ) , and major CVD ( 0·86 , 0·78 - 0·93 ; p<0·001 for trend  ) . Higher physical activity was associated with lower risk of CVD and mortality  in high-income , middle-income , and low-income countries . The adjusted population attributable fraction for not meeting the physical activity guidelines was 8·0 % for mortality and 4·6 % for major CVD , and for not meeting high physical activity was 13·0 % for mortality and 9·5 % for major CVD . Both recreational and non-recreational physical activity were associated with benefits . INTERPRETATION Higher recreational and non-recreational physical activity was associated with a lower risk of mortality and CVD events in individuals from low-income , middle-income , and high-income countries . Increasing physical activity is a simple , widely applicable , low cost global strategy that could reduce deaths and CVD in middle age . FUNDING Population Health Research Institute , the Canadian Institutes of Health Research , Heart and Stroke Foundation of Ontario , Ontario SPOR Support Unit , Ontario Ministry of Health and Long-Term Care , AstraZeneca , Sanofi-Aventis , Boehringer Ingelheim , Servier , GSK , Novartis , King Pharma , and national and local organisations in participating countries that are listed at the end of the Article OBJECTIVE : To examine the association of physical activity and body mass index ( BMI ) , and their combined effect , with the risk of total , cardiovascular disease ( CVD ) and cancer mortality .  DESIGN : Prospect i ve follow-up study .SUBJECTS : In all , 22 528 men and 24 684 women aged 25–64 y at baseline having 7394 deaths during a mean follow-up of 17.7 y . MEASUREMENT : A self-administered question naire data on smoking , socioeconomic factors , physical activity and medical history , together with measured height , weight , blood pressure and serum cholesterol using st and ardized protocol . RESULT : Physically active subjects had significantly lower age-adjusted mortality from cardiovascular , cancer and all causes compared with sedentary ones . Further adjustment for smoking , systolic blood pressure , cholesterol , BMI , diabetes and education affected the results only slightly . Obese subjects ( BMI ≥30 kg/m2 ) had significantly higher cardiovascular and total mortality than the normal weight ( 18.5≤ BMI < 25 kg/m2 ) subjects . Part of increased mortality among obese subjects was mediated through obesity-related cardiovascular risk factors . BMI had an inverse association with cancer mortality among men and almost significant direct association among women . Total mortality was also increased among the lean ( BMI < 18.5 kg/m2 ) subjects . However , less than 0.3 % of deaths were attributed to low body weight , whereas in men 5.5 % and in women 17.7 % of deaths were attributed to obesity . CONCLUSION : Regular physical activity and normal weight are both important indicators for a decreased risk of mortality from all causes , CVD and cancer . Physical activity had a strong independent effect on mortality , whereas the effect of BMI was partly mediated through other obesity-related risk factors OBJECTIVE We evaluated the hypothesis that higher levels of total daily physical activity can eliminate the increased mortality rate associated with overweight and obesity . DESIGN Population -based prospect i ve cohort study . SETTING Central Sweden . SUBJECTS A total of 37,633 men at baseline 45 - 79 years of age and free of known cancer and cardiovascular disease and diabetes completed a  self-administered life-style question naire , which included questions on body-mass index ( BMI ) and physical activity . During 9.7 years of follow-up , we identified a total of 4086 deaths . MAIN OUTCOME MEASURES Mortality rate ratios ( RRs ) . RESULTS Compared to men who were lean ( BMI < 25 kg m(-2 ) ) and active ( top tertile of total physical activity level ) the multivariable adjusted RRs ( 95 % confidence interval ) of death from all causes were 1.44 ( 1.11 - 1.86 ) for obese ( BMI > or = 30 kg m(-2 ) ) and active men , 1.54 ( 1.34 - 1.77 ) for lean ( BMI < 25 kg m(-2 ) ) but inactive ( bottom tertile ) men , and 1.81 ( 1.48 - 2.23 ) for obese-inactive men . After excluding the first 3 years of follow-up , current and former smokers , those who had lost weight from age 20 years to age at baseline , and heavy manual workers , the adjusted RRs of death from all causes were 1.65 ( 1.20 - 2.27 ) for overweight-to-obese and active men , 2.15 ( 1.59 - 2.91 ) for lean-inactive men , and 2.04 ( 1.52 - 2.74 ) for overweight-to-obese and inactive men compared to lean-active men . CONCLUSIONS We conclude that both overweight and physical inactivity are important predictors of mortality . Our findings do not support the hypothesis that a higher level of physical activity compensates the excess mortality associated with overweight and obesity The global epidemic of obesity and physical inactivity may have detrimental implication s for young people ’s  cognitive function and academic achievement . This prospect i ve study investigated whether childhood motor function predicts later academic achievement via physical activity , fitness , and obesity . The study sample included 8,061 children from the Northern Finl and Birth Cohort 1986 , which contains data about parent-reported motor function at age 8 y and self-reported physical activity , predicted cardiorespiratory fitness ( cycle ergometer test ) , obesity ( body weight and height ) , and academic achievement ( grade s ) at age 16 y.  Structural equation models with unst and ardized ( B ) and st and ardized ( β ) coefficients were used to test whether , and to what extent , physical activity , cardiorespiratory fitness , and obesity at age 16 mediated the association between childhood motor function and adolescents ’ academic achievement . Physical activity was associated with a higher grade -point average , and obesity was associated with a lower grade -point average in adolescence . Furthermore , compromised motor function in childhood had a negative indirect effect on adolescents ’ academic achievement via physical inactivity ( B = –0.023 , 95 % confidence interval = –0.031 , –0.015 ) and obesity ( B = –0.025 , 95 % confidence interval = –0.039 , –0.011 ) , but not via cardiorespiratory fitness . These results suggest that physical activity and obesity may mediate the association between childhood motor function and adolescents ’ academic achievement . Compromised motor function in childhood may represent an important factor driving the effects of obesity and physical inactivity on academic underachievement Background Effective interventions to prevent overweight and obesity in children are urgently needed especially in inner-city neighbourhoods where prevalence of overweight and inactivity among primary school children is high . A school based intervention was developed aim ing at the reduction of overweight and inactivity in these children by addressing both behavioural and environmental determinants . Methods / design The main components of the intervention ( Lekker Fit ! ) are the re-establishment of a professional physical education teacher ; three ( instead of two ) PE classes per week ; additional sport and play activities outside school hours ; fitness testing ; classroom education on healthy nutrition , active living and healthy lifestyle choices ; and the involvement of parents . The effectiveness of the intervention is evaluated through a cluster r and omized controlled trial in 20 primary schools among grade s 3 through 8 ( 6–12 year olds ) . Primary outcome measures are BMI , waist circumference and fitness . Secondary outcome measures are assessed in a subgroup of grade 6–8 pupils ( 9–12 year olds ) through classroom question naires and constitute of nutrition and physical activity behaviours and behavioural determinants . Multilevel regression analyses are used to study differences in outcomes between children in the intervention schools and in  control schools , taking clustering of children within schools into account . Discussion Hypotheses are that the intervention results in a lower prevalence of children being overweight and an improved mean fitness score , in comparison with a control group where the intervention is not implemented . The results of our study will contribute to the discussion on the role of physical education and physical activity in the school curriculum . Trial registration [ IS RCT N84383524 Physical activity has been shown to reduce colorectal cancer risk . However , the association of physical activity levels separately with colon and rectum cancer mortality is less clear . We included 226 089 Korean in a large prospect i ve cohort study . We assessed the associations of  physical activity levels ( length , frequency , and intensity ) with colon and rectum cancer mortality using Cox proportional hazards model . Men , but not women , who had regular physical activity showed a lower risk of death from colon cancer . The association for high intensity of physical activity  was borderline significant in men ( hazard ratio 0.67 ; 95 % CI = 0.45 - 1.00 for > 17.5 MET-hour/week ) . The associations were largely consistent among those aged < 55 years , body mass index < 25 kg/m2 , low high-density lipoprotein cholesterol , current smoker , and without hypertension or history of cardiovascular disease . In conclusion , higher length or intensity of physical activity  decreased colon , but not rectum cancer mortality in men .  Regular physical activity may have beneficial effects on colon cancer survival BACKGROUND The influence of excess body weight on the risk of death from  cancer  has not been fully characterized . METHODS In a prospect ively studied population of more than 900,000 U.S. adults ( 404,576 men and 495,477 women ) who were free of cancer at enrollment in 1982 , there were 57,145 deaths from cancer during 16 years of follow-up . We examined the relation in men and women between the body-mass index in 1982 and the risk of death from all cancers and from cancers at individual sites , while controlling for other risk factors in multivariate proportional-hazards models . We calculated the proportion of all deaths from cancer that was attributable to overweight and obesity in the U.S. population on the basis of risk estimates from the current study and national estimates of the prevalence of overweight and obesity in the U.S. adult population . RESULTS The heaviest members of this cohort ( those with a body-mass index [ the weight in kilograms divided by the square of the height in meters ] of at least 40 ) had death rates from all cancers combined that were 52 percent higher ( for men ) and 62 percent higher ( for women ) than the rates in men and women of normal weight . For men , the relative risk of death was 1.52 ( 95 percent confidence interval , 1.13 to 2.05 ) ; for women , the relative risk was 1.62 ( 95 percent confidence interval , 1.40 to 1.87 ) . In both men and women , body-mass index was also significantly associated with higher rates of death due to cancer of the esophagus , colon and rectum , liver , gallbladder , pancreas , and kidney ; the same was true for death due to non-Hodgkin 's lymphoma and multiple myeloma . Significant trends of increasing risk with higher body-mass-index values were observed for death from cancers of the stomach and prostate in men and for death from cancers of the breast , uterus , cervix , and ovary in women . On the basis of associations observed in this study , we estimate that current patterns of overweight and obesity in the United States could account for 14 percent of all deaths from cancer in men and 20 percent of those in women . CONCLUSIONS Increased body weight was associated with increased death rates for all cancers combined and for cancers at multiple specific sites Physical activity ( PA ) could be protective against  hypertension  , atherosclerosis , coronary heart disease and cardiovascular disease . This quantitative study assessed the association between a PA intervention and three anthropometric parameters ( weight , body mass index , body fat ) and four physiological parameters ( cholesterol level , systolic blood pressure , diastolic blood pressure , heart rate ) among secondary school pupils ( N = 160 ) in Egypt through the school term . The pupils were r and omised to an intervention group ( 80 pupils ) and controls ( 80 pupils ) . Measurements were obtained for all pupils twice : at baseline ; and then again after three months . The PA intervention programme comprised an ‘ afterschool ’ one hour of moderate exercise three times a week for three months . Both the controls and the intervention pupils attended the ‘ normal ’ exercise schedule provided by the school ; in addition , the intervention group attended afterschool PA programme from about 2–3 o’clock in the afternoon . At baseline , employing pupil ’s BMI , 27.5 % and 28.8 % of the intervention and control pupils respectively were classified as overweight . After three months , the percentage of overweight decreased to 12.5 % in the intervention pupils , while it increased to 37.3 % in the controls . At the end of the three months period , there were significant improvements across most anthropometric and physiological parameters of the intervention pupils when compared with the control children . The correlation coefficient of the improvements for the boys and the girls was 0.97 , indicating clearly that the intervention was having nearly the same beneficial effect for boys and girls . A moderate PA programme for a modest period of 3 months could be effective in maintaining or enhancing pupil ’s anthropometric and physiological parameters in comparison to the controls where there was deterioration in both parameters . Policy makers and secondary schools in Egypt might need to pay more attention to PA programmes conducted on school days , in order to motivate pupils to attend such programmes . There is also an urgent need to look at current PA systems within schools in Egypt in order to assess PA outside school times Background Childhood obesity is the result of a long lasting imbalance between energy intake and energy expenditure . A major contributing factor is physical inactivity which is closely linked to bone health , cardiovascular disease risk , fitness and psychological factors . The school seems to provide an excellent setting to enhance levels of  physical activity ( PA ) .  However , there is insufficient data from previous school-based intervention trials on how to enhance overall PA . It is also unknown whether an intervention aim ed at increasing PA is effective in improving the children 's health . The purpose of this paper is to outline the design of a school-based r and omized , controlled trial ( RCT ) aim ing to increase overall PA and to improve fitness and health in 6- to 13-year-old children . Methods / Design 15 schools were r and omized to the intervention ( n = 9 ) or the control ( n = 6 ) group , stratified by geographic region ( urban vs. rural ) and by age ( 1st and 5th grade ) . Participation was given for all children in the intervention group since in this group the intervention was part of the normal school curriculum . The intervention during one academic year consisted of : 1 . two additional physical education classes per week given by trained physical education teachers adding up to a total of five PA classes per week , 2 . short PA breaks ( 2–5 min each ) during academic lessons , 3 . PA home work , and 4 . adaptation of recreational areas around the school . All children underwent  anthropometric measurements , blood pressure assessment , fitness testing , measurement of PA  and they filled out question naires . At least 70 % of all children agreed to blood sampling and measurements of body composition and bone mineral measurements by dual energy x-ray absorptiometry . The primary endpoints of the study after one year were an increase in total PA by accelerometry , an increase in aerobic fitness measured by the 20 m shuttle run , a decrease in percent body fat derived from skinfold measurements and an increase in quality of life as assessed by the child health question naire in the intervention group compared to the control group . Secondary outcomes were overall fitness , differences in body composition including body fat distribution , cardiovascular risk factors , psychosocial health , bone mineral content and density of femur , lumbar spine and total body and food intake . Discussion Our preliminary data suggest that the children were representative of Swiss children with respect to sex , socio-demographic status , and body mass index . Short-term results can be expected by the beginning of 2007 . We hypothesized that our intervention will lead to an increase in PA , fitness and overall health . Based on our data , we aim to provide important information regarding the influence of such an intervention on these outcome measures in school-aged children and to provide nationwide guidelines to improve PA in children
There was some evidence that school-based physical activity interventions had a positive impact on four of the nine outcome measures .
Specifically positive effects were observed for duration of physical activity , television viewing , VO2 max , and blood cholesterol .
Generally , school-based interventions had little effect on physical activity rates , systolic and diastolic blood pressure , BMI , and pulse rate .
At a minimum , a combination of printed educational material s and changes to the school curriculum that promote physical activity result ed in positive effects .
Few changes in outcomes were observed in this up date with the exception of blood cholesterol and physical activity rates .
For example blood cholesterol was no longer positively impacted upon by school-based physical activity interventions .
The evidence suggests the ongoing implementation of school-based physical activity interventions at this time , given the positive effects on behavior and one physical health status measure .
BACKGROUND The World Health Organization ( WHO ) estimates that 1.9 million deaths worldwide are attributable to physical inactivity and at least 2.6 million deaths are a result of being overweight or obese .
In addition , WHO estimates that physical inactivity causes 10 % to 16 % of cases each of breast cancer , colon , and rectal cancers as well as type 2 diabetes , and 22 % of coronary heart disease and the burden of these and other chronic diseases has rapidly increased in recent decades .
OBJECTIVES The purpose of this systematic review was to summarize the evidence of the effectiveness of school-based interventions in promoting physical activity and fitness in children and adolescents .