the prevalence of childhood obesity is increasing at an alarming rate , and many local governments have enacted policies to increase physical activity in schools as a way to fight childhood obesity . determining the prevalence of overweight and obesity in children is of obvious importance , because it has been reported that more than 60% of obese children have one or more cardiovascular risk factors such as hyperinsulinemia , glucose intolerance , dyslipidemia , or hypertension that are directly or indirectly related to obesity . overweight children are reported to have higher fasting glucose levels , and they produce more insulin after a glucose challenge . an increased body mass index ( bmi ) in adolescence predicts elevated adult mortality and cardiovascular disease rates , even if the excessive body weight is lost . childhood obesity is reported to be an important predictor of adult obesity , as more than 60% of children who are overweight before puberty will be overweight in early adulthood as well . this issue is of particular concern as it will probably reduce the average age at which noncommunicable diseases become apparent , thus greatly increasing the burden on health services which will have to provide treatment during most of their adult life . unfortunately , children are now more frequently subject to many obesity - related health conditions than before , because of automated and inactive lifestyle . most studies in this regard indicate that one in four children aged 614 years is overweight in developed and developing countries , which ranges from 11% to 39% . although the prevalence of overweight and obesity was reported significantly different between genders , as some studies reported higher prevalence in girls , and some in boys , some studies have reported similar prevalence in both genders . based on published data in a health survey conducted in 1999 , prevalence rates of overweight and obesity for school - aged iranian children was 13.6% . low levels of physical activity and health - related physical fitness represented by cardio - respiratory endurance have been reported in some studies , but little data have been recorded regarding the middle school students in the city of isfahan . there are only a few data available about the prevalence of overweight and obesity among children in the city of isfahan , the second large city in iran . as we need solid base to implement preventive and treatment strategies of heath care organizations , the purpose of this study was to determine the prevalence of obesity and overweight in 1214 years old students in city of isfahan . this descriptive survey was performed among 12,946 students aged 1214 years in isfahan county , from whom 2415 were boys and 10,531 girls , respectively . a number of 30 schools were identified and randomly selected from isfahan city on a proportional basis . principals of the schools were contacted with the aims of the study explained to both physical education teachers and school administrators . agreement forms for parents were distributed , and once schools and parents had agreed to let their children participate in the study , they completed a testing participation and medical history questionnaire and were informed that they could withdraw from the study at any time . participants were in good health , free from musculoskeletal dysfunctions , metabolic disorders , and heart diseases . each child underwent a 1-day testing session in which anthropometric assessment tests were carried out . heights were measured using a stadiometer ( novin company , tehran , iran ) to the nearest 0.5 cm while body weights were obtained to the nearest 0.2 kg using a calibrated balance beam scale ( novin , iran ) . descriptive statistics was conducted on all the measured variables , and percentile ranks for bmi of subjects were computed based on sex categories . data were analyzed by the spss - pc software ( version 20.0 ) ibm spss inc . this descriptive survey was performed among 12,946 students aged 1214 years in isfahan county , from whom 2415 were boys and 10,531 girls , respectively . a number of 30 schools were identified and randomly selected from isfahan city on a proportional basis . principals of the schools were contacted with the aims of the study explained to both physical education teachers and school administrators . agreement forms for parents were distributed , and once schools and parents had agreed to let their children participate in the study , they completed a testing participation and medical history questionnaire and were informed that they could withdraw from the study at any time . participants were in good health , free from musculoskeletal dysfunctions , metabolic disorders , and heart diseases . each child underwent a 1-day testing session in which anthropometric assessment tests were carried out . heights were measured using a stadiometer ( novin company , tehran , iran ) to the nearest 0.5 cm while body weights were obtained to the nearest 0.2 kg using a calibrated balance beam scale ( novin , iran ) . descriptive statistics was conducted on all the measured variables , and percentile ranks for bmi of subjects were computed based on sex categories . data were analyzed by the spss - pc software ( version 20.0 ) ibm spss inc . the descriptive data of the measured variables such as the mean of weight , height , and bmi of subjects are shown in table 1 . in tables 2 and 3 table 4 shows the prevalence of overweight and obesity in children specified according to the 85 and 95 percentile from centers for disease control and prevention ( cdc ) criteria . prevalence of overweight based on cdc criteria varied by age from 15.3% to 26.9% in boys and 12.929.9% in girls , and prevalence of obesity varied from 14.8% to 33.7% and 1529.9% in boys and girls , respectively . descriptive data related to measured variables in students ( n=12,946 ) bmi percentiles of girl students aged 1214 years in the city of isfahan bmi percentiles in boy students aged 12 - 14 years in the city of isfahan distribution of body composition based on cdc criteria in 12 - 14 years students the data obtained from the present study demonstrated that the prevalence of overweight was not similar among boys and girls ; as girls had higher bmi levels compared to their male counterparts in all age categories . since , we did not assess the stage of puberty of subjects , and there are probably gender differences in sexual maturation of them , it is necessary to consider some cautions for interpretation of results . when children , who were obese and overweight by bmi criteria , were considered together , more alarming data were generated as higher values of overweight and obese children found in this study ( 45% for boys and 43% girls ) compared to other studies . al - nakeeb et al . indicated that over 37% of boys and girls from birmingham fell into overweight and obese classifications , with one in 5 ( 22% ) children having more than 30% body - fat . they also reported that 71% of children had a percentage of body - fat in excess of 20% , which is recognized as the upper end of the optimal range for this age - group . in a study that held on mexican children , authors reported that based on the cdc percentiles , overweight prevalence in different age groups varied from 10.8% to 16.1% in boys and from 14.3% to 19.1% in girls , whereas obesity prevalence were from 9.2% to 14.7% in boys and 6.8% to 10.6% in girls . the prevalence of obesity among children from spain was 58% , while it was 7.9% among boys and 4.7% among girls in qatari adolescents . there is little evidence of significant age differences in overweight or obesity among iranian middle school students , either for boys or girls , but analysis of data in current studies indicates that there is a tendency for 12-year - old girls and boys to have lower levels of overweight or obesity than those aged 14 years that is consistent with previous studies . goran et al . reported that boys have a higher prevalence of overweight and obesity than girls in almost all countries involved in study at all ages , except for a few exceptions like in 11-year - olds in denmark , france , the netherlands and the united kingdom and in 13-year - olds in ireland , where girls are more frequently overweight and obese than boys . in 11-year - olds , the prevalence of overweight or obesity is 16% among boys and 12% among girls ; this difference persists at 13 years of age , where the prevalence is 15% in boys and 10% in girls and continues in 15-year - olds . there were no countries or areas in which the prevalence in boys in 2001 was below 5% ; and it increased in all countries and areas with obesity and overweight prevalence lower than 10% in 2001 except the netherlands . among twelve countries or areas where the prevalence in boys was > 15% in 2001 , over the period , a fall in prevalence was seen in only six . the prevalence continued to increase in two of the six countries ( greece and italy ) where the prevalence was > 20% in 2001 , although it did begin to fall in malta , portugal , spain , and the united kingdom . these trends reveal the fact that despite many international and national efforts , their positive consequences have not become apparent . many initiatives have taken place in the last few years , including legislation , action plans , and guidelines for preventing obesity . the prevalence and temporal trends in obesity reveal the need for a greater commitment on the part of countries in order to put these recommendations and tools into practice to address the main driving forces of this health burden , including nutrition , physical activity , and lifestyle . much effort needs to be dedicated in the next few years to make sure that the instruments available are used and implemented , as well as assessing their effectiveness through continued monitoring and assessment of their effects . hence , it is not surprising that people who have sedentary lifestyles also have low levels of fitness and excessive body fat . therefore , it appears that the goal of optimal altering of adiposity in children should begin with increasing physical activity and fitness , which , in turn , will lead to reductions in body - fat . moreover , children who improve their cardiovascular fitness during childhood have less overall adiposity and less abdominal adiposity than their counterparts during adolescence and adulthood . participation in vigorous physical activities has been shown to relate inversely to fat deposition in both children and adults . the primary behavioral and environmental factors causing obesity are food - consumption patterns , sedentary behavior , and socioeconomic status . the gradual increase in body weight that leads to obesity is the consequence of a prolonged positive energy balance , meaning when energy intake exceeds energy loss . there are many factors that can influence energy balance and therefore be identified as contributors to the current obesity epidemic in children , with biological , behavioral , environmental , and social being most cited . although the relative contribution of energy intake versus energy loss to the obesity epidemic is a source of continuing debate , available data clearly indicate that physical activity plays an integral role in the prevention of obesity . inactivity is only one of the factors interconnected with obesity , and perhaps it is one of the easiest to modify . guidelines for physical activity in children and youth recommended to participate in moderate to vigorous physical activities for at least 60 min a day for health promotion and from a weight - control perspective . recent studies suggest that inactivity is only one of the factors interconnected with obesity ; however , it is perhaps one of the easiest to modify . guidelines for physical activity in youths recommend involvement in moderate to vigorous physical activities for at least 60 min a day for health promotion and from a weight - control perspective . according to the results of the present study and the fact that iranian academic curriculum includes only 90-min physical activity for students per week , initiatives should be put forward to promote physical activity in iranian children in both school and out - of - school environment . the clear understanding of the prevalence of overweight and obesity of children in the present study may not be possible due to several limitations . it seems that more accurate measures of body composition are required to determine the levels of overweight and obesity . furthermore , we faced some limitations in selection and participation of male students compared to their female counterparts ; hence more girl students were participated in this study . last but not least , for establishing a more relevant standards for childhood overweight and obesity it can be said that although measurement of skinfold is more time - consuming , it is a relatively strong substitute for bmi for measuring the percentage of body - fat . the clear understanding of the prevalence of overweight and obesity of children in the present study may not be possible due to several limitations . it seems that more accurate measures of body composition are required to determine the levels of overweight and obesity . furthermore , we faced some limitations in selection and participation of male students compared to their female counterparts ; hence more girl students were participated in this study . last but not least , for establishing a more relevant standards for childhood overweight and obesity it can be said that although measurement of skinfold is more time - consuming , it is a relatively strong substitute for bmi for measuring the percentage of body - fat . our results suggest that aerobic fitness as an indicator of physical activity is linked to the increased level of adiposity in children . according to the results of the present study and the fact that iranian academic curriculum includes only 90-min physical activity per week , initiatives should be put forward to promote physical activity in iranian children in both school and out - of - school environments .
background : childhood obesity is a worldwide major public health problem in both developed and developing countries . the purpose of this study was to determine the prevalence of obesity and overweight in 12 - 14-year - old students in the city of isfahan.methods:this study was conducted among 10,531 girls and 2415 boys aged 1214 years in the city of isfahan . 
 percentage of children in the corresponding body mass index ( bmi ) categories for overweight and obesity ( specified by the centers for disease control and prevention criteria percentiles ) were assessed , based on preventive plan of inactivity in children and youth of isfahan province.results:findings revealed that prevalence of overweight in children varied by age from 15.3% to 26.9% in boys and 12.9% to 29.9% in girls , and prevalence of obesity varied from 14.8% to 33.7% and 15% to 29.9% in boys and girls , respectively . 
 percentile norms for bmi of subjects were computed based on sex categories.conclusions:to conclude , results of the study revealed that subjects have approximately the same percentage of overweight / obesity compared to other children have been studied ; however , in comparison to previous studies , a higher rate was witnessed in grade 8 boy students . 
 these situations indicate that there are needs to implement some intervention programs , as well as management policies .