genetic factors , 
 medical conditions , medications , and environmental factors are the most common causes of 
 childhood obesity , which is usually managed through a diet regimen , exercise , and surgical 
 treatment1,2,3
. the prevalence of overweight and obese individuals is increasing at an alarming rate , and 
 obesity has become one of the most important avoidable and independent risk factors for 
 morbidity and mortality4 .
a successful weight management program must include dietary adjustments , increased physical 
 activity , and behavior modifications .
nutrition modification should take into account the 
 diet s energy content , composition , and suitability for individual patients5 .
the european standards for energy - restricted diets have been established , but leave little 
 flexibility for change .
three categories prevail : very low - calorie diets [ 450800  kcal ] , 
 low - calorie diets [ 8001200  kcal ] , and meal replacements [ 200400  kcal]6 .
obesity in children has been associated with lower levels of physical activity and fitness . 

research examining maximal oxygen consumption ( vo2 max ) in obese and non - obese 
 children indicates a significant difference in exercise tolerance7 .
physical activity and exercise are essential elements in 
 obesity treatment , and regular physical activity has also been shown to lessen the burden of 
 obesity - related comorbidities8 .
physical activity , without a reduction in calorie intake , usually has no relevant effect on 
 weight .
although it is possible to lose weight through physical activity alone , the amount 
 of physical activity required for substantial weight loss is well beyond what is feasible 
 for most people in today s world .
for instance , it would take more than 12 hours of very 
 vigorous activity per day for children to achieve the desired weight loss9 .
the purpose of this study was to determine changes in cardiopulmonary functions after 
 aerobic and anaerobic exercise training in obese participants , with the aim to identify the 
 most appropriate types of exercise training programs for these individuals .
forty obese subjects , whose ages ranged from 18 to 25  years , participated in this study . 
 subjects suffering from any cardiovascular , pulmonary , orthopedic , or neurological disorders 
 were excluded from the study .
patients were divided into 2 equal groups : group a received 
 aerobic treadmill walking exercise training for 3 months , at a frequency of 3 sessions per 
 week , in addition to dietary measures .
the second group , group b , received anaerobic 
 exercise training for 3 months , at a frequency of 3 sessions per week , in addition to 
 dietary measures .
all participants were free to withdraw from the study at any time . in the 
 event of occurrence of any adverse effects
, the experiment would have been discontinued , and 
 the human subjects review board was informed regarding this .
however , no adverse effects 
 occurred , and data of all participants were available for analysis .
this study was approved 
 by the ethics committee , and all participants gave their informed consent .
this study was 
 conducted at the king abdulaziz university hospital in saudi arabia . cardiopulmonary exercise test unit ( cpet ) : ( zan 800 , germany ) .
the cpet consisted of a 
 breath gas ( o2 and co2 ) analyzer , an 
 electronic treadmill , a 12-channel electrocardiogram , ( ecg ) monitor , a gas bottle , and a 
 mask with a diaphragm to analyze gas , which was used to measure vo2 max and 
 in - exercise training .
the speed and inclination of the treadmill were controlled by 
 pre - selected software ( standard bruce protocol ) .
this 
 unit was calibrated daily , as its speed , inclination , and timer are adjustable .
pulsometer ( tunturt tpm-400 , japan ) : this was used to detect pulse rate before , during , and 
 after exercise .
a spirometer ( schiller - spirovit sp-10 , switzerland ) was used to measure 
 maximum voluntary ventilation ( mvv ) .
a mercury sphygmomanometer ( diplomat , presameter ) and 
 stethoscope ( riester , duplex , germany ) were used to measure blood pressure before and after 
 exercise training sessions . before starting the study
, each participant completed a consent form as an agreement to be 
 included in the present study .
additionally , before initiation of the exercise training 
 program , each subject was examined medically by a physician in order to exclude subjects 
 with any of the medical problems listed above in the exclusion criteria . a brief description 
 of the tasks expected during the test was provided to the subjects . before conducting the exercise tolerance test ,
all subjects were asked to visit the 
 laboratory to get familiar with the equipment for ensuring cooperation during the test .
, in accordance 
 with the standard bruce protocol , which consisted of a warm - up phase , 5 active phases , and a 
 recovery phase
. measurements of systolic blood pressure ( sbp ) , diastolic blood pressure ( dbp ) , heart rate 
 ( hr ) , mvv , vo2 max , and body mass index ( bmi ) were obtained for both groups 
 before and after the exercise program . the aerobic treadmill - based training program ( zan 800 , made in germany )
was started with a 
 5-minute warm - up phase performed on the treadmill at a low load .
the active phase of the 
 training session was gradually increased from 20 to 30 minutes in the form of 
 walking / running on the electronic treadmill with zero inclination 3 times per week for 12 
 weeks , its intensity being increased gradually from 60% to 70% of the maximum hr ( hrmax ) 
 achieved in a reference , which was performed in accordance with a modified bruce protocol . 

the anaerobic 
 treadmill - based training program ( zan 800 , made in germany ) was started with a 5-minute 
 warm - up phase performed on the treadmill at a low load .
initially , the active phase of the 
 training session was 2 minutes long , and this was gradually increased by 5 seconds in each 
 session until 3 minutes , followed by rest for 2 minutes ; this was repeated 5 times during 
 each session in the form of running on the electronic treadmill , with a gradual increase 
 from 70% to 80% of the hrmax , according to a modified bruce protocol .
the interview - based food survey was administered to all patients by dieticians to identify 
 previous food habits and possible anomalies in dietary behavior .
the prescribed low - calorie 
 diet was balanced , with 15% as protein , 3035% as fat , and 5055% as carbohydrates on 
 average , in order to provide all study participants with approximately 1,000 calories daily 
 for 2 months .
the prescribed diet included breakfast consisting of 2 boiled eggs ( 80 calories ) , 50  g 
 cheese ( 100 calories ) , and 1 slice of bread ( 105 calories ) ; and lunch consisting of 2 pieces 
 ( 100  g ) of boiled meat ( 240 calories ) or chicken ( 300 calories ) , 500  g salad ( 105 calorie ) , 
 300  g boiled vegetables ( 110 calories ) , and 100  g banana ( 100 calories ) .
however , the dinner 
 consisted of only 200  g skimmed milk ( 120 calories ) .
we checked that the food was eaten as 3 
 daily meals , and we emphasized the need to have a substantial breakfast .
the two groups 
 underwent an identical dietary monitoring program with an initial consultation , and with one 
 check - up in the middle of the program and another during the final sessions by a dietician 
 who was blinded to the type of program the subject had followed .
the mean values of sbp , 
 dbp , hr , mvv , myocardial oxygen consumption , and bmi were obtained for both groups before 
 and after the exercise program .
forty obese subjects , whose ages ranged from 18 to 25  years , were divided into 2 equal 
 groups : group a received aerobic exercise training for 3 months in addition to dietary 
 measures , and group b received anaerobic exercise training for 3 months in addition to 
 dietary measures . the mean bmi , sbp , dbp , and hr values were significantly decreased , 
 whereas the mean mvv and vo2 max values were significantly increased in group a 
 after treatment .
the mean bmi , sbp , dbp , hr , and vo2 max values not show a 
 significant change , and the mean mvv values were significantly increased in group b after 
 treatment ( tables 1table 1.mean values and significance of measured parameters before and after treatment in 
 group aitembmi(kg / m)sbp(mmhg)dbp(mmhg)hr(beats / min)mvv(l / min)vo2 max.(l / min / kg)meansdbefore36.453.361365.987.54.482.12.796.210.83.350.64after30.012.56124.56.880.15.0274.33.8126.616.63.920.53sbp : systolic blood pressure , dbp : diastolic blood pressure , hr : heart rate , mvv : 
 maximum voluntary ventilation , bmi : body mass index , vo2 max .
: maximal 
 oxygen consumption , 2table 2.mean values and significance of measured parameters before and after treatment in 
 group bitembmi(kg / m)sbp(mmhg)dbp(mmhg)hr(beats / min)mvv(l / min)vo2 max(l / min / kg)meansdbefore35.953.72136.54.8884.181.63.698.027.73.420.75after33.542.26136.45.888.53.6824.6104.411.93.610.82sbp : systolic blood pressure , dbp : diastolic blood pressure , hr : heart rate , mvv : 
 maximum voluntary ventilation , bmi : body mass index , vo2 max : maximal 
 oxygen consumption , 3table 3.comparison of mean values and significance of measured parameters after treatment 
 between groupsitembmi(kg / m)sbp(mmhg)dbp(mmhg)hr(beats / min)mvv(l / min)vo2 max(l / min / kg)meansdgroup ( a)30.012.56124.56.880.15.0274.33.8126.616.63.920.53group ( b)33.542.26136.55.888.53.6824.6104.411.93.610.82sbp : systolic blood pressure , dbp : diastolic blood pressure , hr : heart rate , mvv : 
 maximum voluntary ventilation , bmi : body mass index , vo2 max : maximal 
 oxygen consumption ) .
sbp : systolic blood pressure , dbp : diastolic blood pressure , hr : heart rate , mvv : 
 maximum voluntary ventilation , bmi : body mass index , vo2 max . :
maximal 
 oxygen consumption sbp : systolic blood pressure , dbp : diastolic blood pressure , hr : heart rate , mvv : 
 maximum voluntary ventilation , bmi : body mass index , vo2 max : maximal 
 oxygen consumption sbp : systolic blood pressure , dbp : diastolic blood pressure , hr : heart rate , mvv : 
 maximum voluntary ventilation , bmi : body mass index , vo2 max : maximal 
 oxygen consumption
in this study , a significant reduction in bmi was observed in the aerobic exercise group . 

this result is supported by previous studies that have reported a significant reduction in 
 bmi with aerobic exercise , which is associated with subsequent cardiovascular risk factors ; 
 this reduction therefore decreases the risk of cardiovascular disease in these subjects13 , 14 .
the results also indicated that there was a significant increase in mvv in both the aerobic 
 exercise group and the anaerobic exercise group , where the aerobic exercise group obtained a 
 greater increase in mvv than the anaerobic exercise group .
this result is supported by a 
 previous study that reported that aerobic training induces significant physiological 
 adaptations in the cardio - respiratory system of middle - aged men .
the best markers of these 
 adaptations were the smaller sympathetic tachycardia at comparable workloads and the 
 improvement of oxygen transport , as documented by the increase in the anaerobic threshold 
 and vo2 peak during dynamic exercise15 .
this result was also supported by a study comparing 
 cardiopulmonary function between a moderate exercise program and a severe exercise program ; 
 a significant improvement in vo2 max and mvv was reported after both types of 
 exercise16 .
the results also indicated 
 that there was a significant reduction in hr , sbp , and dbp at the end of the program in the 
 aerobic exercise group .
regular aerobic training induces significant adaptations both at rest and during maximum 
 exercise in a variety of dimensional and functional capacities related to the cardiovascular 
 and respiratory regulation system , thus enhancing the delivery of oxygen to the active 
 muscles .
these changes include decreases in resting and maximal exercise hr and enhanced 
 stroke volume as well as cardiac output17 , 18 .
the reduction of hr , sbp , and dbp in the 
 aerobic exercise group after aerobic training might be due to nitric oxide , an important and 
 potent endothelium - derived relaxing factor that facilitates blood vessel dilatation and 
 decreases vascular resistance19 .
the results of our study also indicated that there were no significant changes in hr or in 
 sbp and dbp in the anaerobic exercise group after completion of anaerobic exercise program , 
 but there was a significant reduction after the aerobic exercise program .
this reflects an 
 increased cardiorespiratory load related to the increased duration of the training session 
 from 20 to 30 minutes .
however , the greater blood flow under the influence of the rise in hr 
 and sbp does not satisfy the increased oxygen requirements during anaerobic exercise .
this 
 explains the significant augmentation of pulmonary ventilation and ventilation capacity in 
 the attempt to satisfy the expanding oxygen transport requirements during maximal exercise . 

participation in heavy resistance anaerobic training over an extended period of time 
 increases cardiac workload , and thus it could not be sustained over an extended period of 
 time20 .
the results concerning myocardial oxygen consumption in our study indicated that there were 
 no significant changes in myocardial oxygen consumption after completion of the anaerobic 
 exercise program .
the improvements in the resting hr and sbp are reflected in the myocardial oxygen 
 consumption in this study .
this improvement in myocardial oxygen consumption might be due to 
 an improvement in endothelium 
additionally , it might be due to the recruitment of coronary collateral vessels and enhanced 
 blood flow with regulation of the vasomotor tone toward vagal modulation .
the myocardial 
 oxygen consumption was lowered after 8 weeks of the training program from 60% to 80% of 
 hrmax .
this improvement might be due to increased peripheral vasodilatation and 
 consequently , a decreased afterload following exercise and a reduction in the adrenergic 
 efferent stimuli21 , 22 .
aerobic exercise improves cardiorespiratory fitness in obese 
 subjects with less cardiac workload as evidenced by the low myocardial oxygen consumption , 
 while anaerobic exercise increases cardiac work and is difficult to maintain for extended 
 periods of time23,24,25,26 , moreover , low - intensity aerobic exercise is less difficult , more 
 easily tolerated , and can be practiced daily over an extended period of time .
 [ purpose ] obesity is a global health problem and is associated with a multitude of 
 complications . 
 this study was designed to determine changes in cardiopulmonary functions 
 after aerobic and anaerobic exercise training in obese subjects . 
 [ subjects and methods ] 
 forty obese subjects , whose ages ranged between 18 and 25  years , were divided into 2 equal 
 groups : group a received aerobic exercise training in addition to dietary measures , and 
 group b received anaerobic exercise training for 3 months in addition to dietary measures . 
 measurements of systolic blood pressure , diastolic blood pressure , heart rate , maximum 
 voluntary ventilation , maximal oxygen consumption , and body mass index were obtained for 
 both groups before and after the exercise program . 
 [ results ] the mean body mass index , 
 systolic blood pressure , diastolic blood pressure , heart rate , and maximal oxygen 
 consumption decreased significantly , whereas the mean maximum voluntary ventilation 
 increased significantly after treatment in group a. the mean maximum voluntary ventilation 
 also increased significantly after treatment in group b. there were significant 
 differences between the mean levels of the investigated parameters in groups a and b after 
 treatment . 
 [ conclusion ] aerobic exercise reduces weight and improves cardiopulmonary 
 fitness in obese subjects better than anaerobic exercise . 
INTRODUCTION
SUBJECTS AND METHODS
RESULTS
DISCUSSION