the present study was a clinical trial one done in teaching hospitals of tabriz university of medical sciences . the study population was all patients under hemodialysis treatment in hemodialysis wards of imam khomeini and sina hospitals surveyed . the inclusion criteria were as following ; patients who were under hemodialysis treatment twice or 3 times a week for at least three months,16 their hemoglobin level was more than 8 mg / dl , they could walk without others help , they had enough musculoskeletal strength for doing exercises . the exclusion criteria were coronary artery diseases and arrhythmia ( for this reason , patients were tested by exercise test ) , severe physical and psychological problems that would prevent their cooperation like multiple sclerosis ( ms ) , schizophrenia , cerebrovascular accident ( cva ) , systolic blood pressure over 200 mmhg , using antidepressant drugs during study and inability to do or continue physical exercises for any reason . all patients were interviewed to fill out the questionnaire of physical and psychological problems that was prepared for mental inspection ( this questionnaire was prepared by combining the physical and psychological aspects of standardized questionnaires such as sf-36 and kidney disease quality of life questionnaire ) . evaluated psychological problems were worriness , hope to future , sadness , happiness , and irritation . physical problems were composed of five parts ; physical function , daily activities , pain and discomfort , sleep , and sexual issues . it was validated through content validity and the reliability was calculated using cronbach 's alpha . then patients were scheduled exercise program on days that they were not under dialysis . at the end of the intervention , they filled out the same questionnaire as before and also filled out the two special questions that were measured by lickert criterion ; 1 . how much had the physical exercise improved the psychological problems ( increasing happiness , and decreasing anxiety  ) . study environment was the hemodialysis wards of imam khomeini and sina hospitals of tabriz university of medical sciences . exercise program was done for 1 hour every session and included ergometer , treadmill and ball playing ( the patients selected one or all of them every session ) . this exercise program was aerobic . in every session before starting exercises , patients vital signs ( blood pressure , pulse and respiration ) were controlled by technicians ( they controlled their pulse during exercises , too ) , then patients warmed up by walking around arena for 10 minutes and doing tensional movement and at the next step , they pedaled by ergo meter , moved on treadmill , or did ball playing , they did them by periodical relaxation for 40 minutes ( the time of relaxation was free for each one ) and they chilled their body like warming up finally . the patients , who confronted any problems , were cured by technicians , but if the problem was serious , they were sent to hospital . survey units were selected based on inclusion criteria . all patients were interviewed to fill out the questionnaire of physical and psychological problems that was prepared for mental inspection ( this questionnaire was prepared by combining the physical and psychological aspects of standardized questionnaires such as sf-36 and kidney disease quality of life questionnaire ) . evaluated psychological problems were worriness , hope to future , sadness , happiness , and irritation . physical problems were composed of five parts ; physical function , daily activities , pain and discomfort , sleep , and sexual issues . it was validated through content validity and the reliability was calculated using cronbach 's alpha . then patients were scheduled exercise program on days that they were not under dialysis . at the end of the intervention , they filled out the same questionnaire as before and also filled out the two special questions that were measured by lickert criterion ; 1 . how much had the physical exercise improved the psychological problems ( increasing happiness , and decreasing anxiety  ) . study environment was the hemodialysis wards of imam khomeini and sina hospitals of tabriz university of medical sciences . exercise program was done for 1 hour every session and included ergometer , treadmill and ball playing ( the patients selected one or all of them every session ) . this exercise program was aerobic . in every session before starting exercises , patients vital signs ( blood pressure , pulse and respiration ) were controlled by technicians ( they controlled their pulse during exercises , too ) , then patients warmed up by walking around arena for 10 minutes and doing tensional movement and at the next step , they pedaled by ergo meter , moved on treadmill , or did ball playing , they did them by periodical relaxation for 40 minutes ( the time of relaxation was free for each one ) and they chilled their body like warming up finally . the patients , who confronted any problems , were cured by technicians , but if the problem was serious , they were sent to hospital . at first , exercise program was done for 43 qualified hemodialysis patients , but eight of them abandoned study in different stages for different reasons . the mean ( sd ) age of patients was 45.47 ( 15.16 ) and the age rang was 16 - 80 years . most of the patients were male ( % 80 ) , married ( % 71.4 ) , and jobless ( % 68.6 ) . 62.9 percents of patients were educated in elementary and primary school , 60 percents were under dialysis three times a week . 82.9 percents did not have the experience of kidney transplantation , 47 percent under hemodialysis for 1 - 5 years , 91.5 percents did not have the regular exercise program before of this study . for comparing the scores of before and after intervention , the paired t - test was used . about physical problems including sleep , pain and discomfort , daily activities , and physical function , there were significant differences between scores of before and after intervention , but in sexual activity , there was not any significant difference between scores of before and after intervention . the results showed that psychological problems improved after doing exercises too ( table 1 ) . physical and psychological problems in hemodialysis patients before and after intervention about first special question , 85.6 percent of patients mentioned an improvement in physical conditions , and only 14.4 percent of them did not express any improvement . about second special question , 91.4 percent of patients expressed an improvement in psychological conditions , and only 8.6 percent of them didnt express any improvement ( table 2 ) . the results showed that regular aerobic physical exercise had beneficial effects on decreasing the physical problems in hemodialysis patients . for example it was distinguished that physical exercise lead to improve in  physical function  and  daily activities  . hemodialysis patients face to many problems such as : muscular weakness , fatigue , muscular contraction that may affect their physical function and daily activities . muscular weakness and atrophy are induced by many factors such as : malnutrition , uremic myopathy , neuropathy , accumulation of toxic matters in muscles , and decreasing of circulation in musculoskeletal system . in the other side , several studies have showed that regular aerobic physical exercise in the days after hemodialysis can improve musculoskeletal function by increasing blood circulation and repelling the toxic matters from muscles , so it lead to improve physical function and daily activities in hemodialysis patients.13 in another study by naish , it was shown that physical exercises would enhance musculoskeletal strength.20 other studies have showed that exercise program ( without using erythropoietin ) can increase blood hematocrit . also it can increase the ejection fraction and improve the heart output.13 so with improving musculoskeletal function , increasing blood hematocrit , improving ejection friction and heart output , we can expect that  physical function  and  daily activities  will be improved . the result showed that physical exercise can improve the sleep pattern in hemodialysis patients . in view of the fact that after physical exercise , the patients have tired feeling , weakness , and sleepy , we can expect that it would facilitate the sleep of the hemodialysis patients.21 nieman said that people , who do exercise regularly , would sleep better and feel tiredness less than others during the day.22 in another study by king in stanford university , he divided some old people who did not exercise before in two groups ( case and control ) ; the control group did aerobic and calisthenics exercise in form of walking 30 - 40 minutes every day for 16 weeks . his results showed that physical exercise caused a high quality sleep , longtime sleep , and need a little time to go to sleep.23 the result showed that physical exercise can improve  pain and discomfort  in hemodialysis patients . one of the most prevalent of the patients pains is musculoskeletal pain that is produced by accumulation of toxic matters , the decrease of circulation in musculoskeletal system , and misbalancing of water and electrolytes.24 it seems that regular physical exercise can improve their pain through increasing of circulation and repelling the toxic matters from muscles . sexual problem was the only physical problem that did not improve significantly after regular aerobic physical exercise . for example the researchers of general schools of harvard in an inquiry on 31000 male , showed that the people who did regular physical exercise had 30% less erectile disorders than those who were inactive . also the women , who did regular physical exercise , had better sexual function . in that study , it was cleared that , 20 minutes regular and daily physical exercise had lead to more suitable sexual response in the women.25 improvement of sexual function in hemodialysis patients is impressed by the physiological and psychological factors ; physical exercise is one of the methods that can improve the sexual function in hemodialysis patients . although in this study sexual function has been improved , but it was not statistically significant . it seems that physical exercise would continue for a long term than 8 weeks , until it can be effective statistically . physical situation  after physical exercise ; even half of them said that it was very high . clase et al showed that exercise program could enhance physical state.26 since several studies showed the beneficial effects of physical exercises such as improvement of musculoskeletal strength , increase of hematocrit , recovery of anemia , decrease of ldl , improvement of daily activities , improvement of neuromuscular function , and improvement in the circulation of small blood vessels in hemodialysis patients , we can expect that physical exercise can improve  physical situation  in them . about the psychological problems and second special question do the hemodialysis patients express any improvement of psychological problems ?  , the results showed that the scores of psychological problems in hemodialysis patients increased significantly after regular aerobic physical exercise . also most of them expressed an improvement in  psychological situation  after physical exercise ; even more than half of them said that this effect was very high . it seems that as 91.5 percents of survey units were not following a particular exercise program , adding a regular exercise program to their daily life and appeared happiness in consequence of it , would recover psychological problems in these patients . namazizadeh wrote that physical exercises had many beneficial effects ; one of them is in the fields of psychological and social problems ; it removes worries , isolation , hopelessness and fear ; it cause the balance of competition and acceptance of principles and standards in daily life ; it makes happiness and gladness that are necessary for continuing and improving of life.17 attention to the results , that physical exercise improves the physical problems ( physical function , daily activities , pain and discomfort , and sleep ) , and psychological problems ( worrieness , hope to future , sadness , happiness , irritation ) , it is suggested that responsible people prepare enough equipment and sport place to these patients . patients should be informed about the importance of exercise and educated a correct and undangerouse way of exercise , and doing it in days after hemodialysis , in order to improve of physical , and psychological problems in hemodialysis patients , and finally enhance their quality of life . nurses as people who have a key role in treatment of patients , can help them to improve and care their health by encouraging them to do exercises . researchers have shown that a body which is inactive or is not so active is in discomfort physically or psychologically . so physical exercises are one of the considerable matters for nurses whose aim is , making physically and psychologically healthy feeling in their patients.27 nurses can perform an importance role in doing exercise in form of active ( exercise is done by patient under nurse 's supervision ) , as helper ( when patient can not do physical exercise individually and the nurse help her / him ) or passive ( is done by the nurse ) . the authors declare that have no conflict of interest in this study and ethical committee approved the study .
background : despite therapeutic effect of hemodialysis in end stage renal disease ( esrd ) patients , these patients encounter different physical and psychological tensional factors . 
 physical exercises have beneficial physical and psychological effects on patients under hemodialysis as one of the accessory therapeutic methods . as few studies 
 have been done about the effects of physical exercise on physical and psychological problems in iran than other countries , we assessed the effect in patients under hemodialysis.methods:for this purpose , 43 qualified hemodialysis patients receiving hemodialysis in hospitals of tabriz university of medical sciences were included , but only 35 patients did the exercises for 8 weeks completely . 
 exercise program was done for 1 hour every session and was composed of ergometer , treadmill and ball playing . before and after intervention data were collected by interview through a synthetic and adjusted questionnaire . at the end of the intervention 
 , two special questions were added about the improvement of physical and psychological problems . 
 paired t - test was used to compare the scores of before and after intervention.results:there were significant differences between scores of before and after intervention considering physical problems including sleep , pain and discomfort , daily activities , and physical function ; but about sexual activity , there was not a significant difference between scores of before and after intervention . 
 psychological problems improved after doing exercises too . about first special question , 85.6% of patients expressed an improvement in physical conditions and about second special question , 91.4% of patients expressed an improvement in psychological conditions.conclusions:since physical exercise improves the physical ( physical function , daily activities , pain and discomfort , sleep ) , and psychological problems , it is suggested that responsible people prepare equipment for these patients , until they do exercise forever . 
 nurses would present them the ways of a correct exercise , and doing it in days after hemodialysis , in order to improve physical , and psychological problems in hemodialysis patients , and finally to enhance their quality of life .