فصلنامه پژوهش در علوم ورزشی
سال پنجم شماره 3 (پیاپی 20، پاییز 1387)

The aim of the present research was study the effect of resistance training on serum leptin in obese men. For this purpose 16 obese male (age 35-48) with 82.96 ± 10.4 Kg average weight voluntarily selected and randomly assigned to two groups: resistance training and control group. Blood samples were taken in fasting state from all subjects. The experimental subjects received resistance training for 13 weeks, 3 sessions per week. In this time, the control group did not receive any treatment. The resistance training was done in circuit fashion with 11 stations. Each training session included 4 sets with 12 maximal repetitions in every station done with 50- 60% intensity of onemaximum repetition (IRM). Results showed that in training group, serum leptin concentration was significantly lower than control group (P<0.05). we concluded that resistance training caused a decrease in leptin level in obese men. This decrease is greater of change that there was in fat mass.

The purpose of this study was to investigate the relationship between attitude and association with parents with anabolic steroids use among men Bodybuilders in Ahwaz. The research methods of this study are descriptive, survey and correlation. The instrument of this research was researcher-made questionnaires. The reliability of this instrument was reported to be satisfactory and validity of questionnaire wereobtained relatively (r=0.7944 r=0.7798). The statistical population of this study was all bodybuilder athletes in Ahwaz that 165 of them selected through staged random sampling. In this study, relationship between attitude and association with parents with anabolic steroids use were studied. In addition relationship between some of individualcharacteristic with Anabolic Steroids was studied. Analyzing the proposed hypotheses at the p<0.05 showed these significant relationship between anabolic steroids use with attitude and education observed. Significant relationship did not report between anabolic steroids use with association with parents, economic statuse and age.

The Purpose of this study was to determine the effect of the ingestion of Nahco3 on Acid-Base balance and performance time in trained male wrestlers during intermittent running to exhaustion. Twenty healthy male wrestlers (17-27 & 60-78 Kg body weight) were participating in exercise training protocol. Subjects were assigned either supplementgroup (n=10) and placebo group (n=10). The supplement group was received Nahco3 in form one capsule (0.065 gr/Kg body weight) while the placebo group was received the same amount of bran rice one hour before the test. Subjects were performed a test on a motor driver treadmill at speeds, 8, 12 and 14 Km/ h and incline 10% grade. Eachphase was consisted of 2 minutes of running which followed by 30 sactive resting period at speeds 4 Km/h (in phase 1), 8 Km/h (phase 2) and in the last phase (phase 3). Subjects ran until to exhaustion. Blood sample was taken before and immediately after the test. Plasma lactate, Ph, Pco2, Po2 and Hco3 were measured. A paired andunpaired t-test were used for data analyzing and significant level was considered at P􀂔 0/05. The results showed that a change in blood gase was not significant. However a decrease in plasma lactate and an increase in running time to exhaustion were observed. It seems that NaHco3 supplementation before the exercise increase running time toexhaustion via reducing the appearance of lactate into blood.

The purpose of this research was to investigate evaluation in physical education course from teacher's viewpoint in girl's middle schools in Iran. The research method was descriptive and survey. The sample of this research was 700 physical education teachers that selected randomly from all of states, witch divided to five regions according totheir geographical conditions. The instrument of this study was researcher – made questionnaire that used to test viewpoint of teachers concerning the evaluation in physical education course. The reliability and validity of this questionnaire obtained relatively (r= 0.89, r=0.63). Descriptive statistic and ANOVA and Tuky are used for dataanalysis. The descriptive data indicated that evaluation in physical education course in girl's middle schools was assessed fairly at five different regions of country. The results revealed that student's performance In physical fitness, sport skills, cognitive and affectivedomains in middle schools did not evaluate the same. Also analysis of hypotheses showed that there were significant differences between current evaluations of physical education course from viewpoint of teachers in different regions of country. Finally we developed a model based on the results of this study, review of literature and evaluation which used other countries and present position of schools in country

The purpose of the present study was to investigate the effects of mental practice on strength and electromyography modification of elbow flexor muscles. Sixteen healthy, untrained subjects (mean ± SD; age=22.5±1.36 years, height=175.18±6.62cm, weigh t=68.78±7.05 and movement imagery ability=20.81±3.71) participated in this study.Subjects were randomly assigned to a mental practice group (n = 8) or control group (n = 8). Mental practice group trained mental contraction of elbow flexion for 4 week (5 day per week); and control group was not trained but participated in all measurement. Mental practice program were included 50 mental maximal voluntary contractions for 2sets of 25 repetitions. Strength and electromyography was measured at pre and post training program. The t –student test was used to determine the statistical difference in variables of study in significant level of p􀂔0.05.The results showed that elbow flexion strength increased by 30 and 5 percent in mental practice and control groupsrespectively (p􀂔0.05). There was significantly difference between mental practice group and control group (p􀂔0.05). Also, EMG signals augmented significantly in elbow flexor muscle and decreased in elbow extensor muscle. It can be concluded that mental practice can increase strength elbow flexor muscles, which strength gain is attributed thetraining-induced changes in programming central nervous system and increases activation level muscle.

The importance of postural control fact to perform the correct daily activities of human or complicated sport activities has been documented, thus it's necessary to assess and identify the level of neuromuscular performance in different age groups or different levelsof sport activities. With respect to the fact that fatigue is an undeniable component of sports, the purpose of this study was to examine the effect of activity related fatigue on postural control. 40 untrained healthy students (age: 21.3±1.5 Yr, weight: 74.2±14.4 kg, height: 170±5.2 cm) volunteered to participate in this study. They completedpre-test, then performed a functional fatiguing protocol (20 min and 7station). Their Rating of Perceived Exertion (RPE) was measured before the first station, the end of third station and exactly after completing the seventh station. The post test was given afterward. A two-way repeated measure, ANOVA was used to determine if asignificant difference could be found in RPE between the two tests. Post-hoc testing (shefe) was run for all of them. The findings demonstrated a significant interaction between time and direction, significant main effects for time (pre and post of fatigue) and direction of SEBT and a significant main effect for RPE that means decrease indynamic postural control after functional fatigue. The results of the study support the hypothesis that functional fatigue decreases dynamic postural control.

The purpose of the present study was to survey the dual task effect on balance and EMG pattern of the muscles. 40 non-athlete students were chosen and were randomly put in 4 equal groups, ten in each one, including motor- stability dual task, cognitive-stability dual task, stability discrete task and control groups.Before the exercise, the groups were classified based on stability index; the first group did stability exercise and ping-pong bat hits simultaneously, the second group did stability exercise and stroop effect, but the third group only did the stability exercise. After doing the exercises, the data were collected in the post-test to consider the amount of changes in balance and EMG (RMSE) in four chosen muscles. The analysis showed that both dual tasks had a significant difference on stability. Motor- stability dual task was better than the cognitive-stability dual task, though. None of the groups had anysignificant effect on EMG after the exercise period. Motor task also caused much more interference on stability and EMG than cognitive one. EMG pattern also showed no significant difference between four selected muscles in a way that there was slightly increase in tibialis anterior and peroneus longus muscles and a slight decrease in gluteusmedius and rectous femoris muscles. Findings showed that the flexibility of attention capacity is related to demands of the task. It can be concluded that effect of practicing a suitable dual task can be effective with decreasing the task demands or autonomy and it makes no difference in related EMG pattern.

The Purpose of this study was to determine the effect of ten weeks resistance training combined with creatine supplementation on bone mineral density (BMD) and association between mascle strength and lean body mass with bone mineral density in untrained young men. In order to, 16 young men (average age 23.2 􀁲 2.4 yrs) were randomizedto recive creatine (0.3g/kg for 7d and 0.05g/kg thereafter) or placebo while participating in resistance training. The training protocol consisted of thrice weekly using three sets of eight to ten repetition at 60-70% of 1-RM for whole-body exercise. Bone mineral density were determined by dual energy X-rayabsorptiometry befor and after training. Result showed that resistance training + supplement and resistance training + placebo caused significant increases (p<0.05) in muscular strength and lean body mass, but had no significant effect on bone mineral density, and in both group there was significant correlation between bench press with arm BMD, and leg press with leg BMD, also in both group there was significant correlation between leg lean body mass with leg BMD (p<0.05), however, all of this corrolations with increases of subjects body weight, strength and lean body mass, become no significant at ten week. In conclusion, these results suggested ten weeks resistance training combined with creatine supplement had no effect on BMD in young men and probably for osteogenic effect of increased loading (increase of muscle strength and mass) resulted of resistance training more time is need, and muscular strength as site specific is the most important predictor of BMD in untrained young men.

This study examined the relationship between general physical fitness, job satisfaction and organization commitment of male physical educators. This study was a kind of descriptive and correlation. Study samples were 235 male physical educators who were selected from 15 education area by using one process cluster sampling. Study toolswere Canadian Award for Physical Fitness test and job satisfaction and organization commitment and individual information questionnaires. Using Pearson correlation test indicated that there were inverse significant relationship between general physical fitness and job satisfaction (P=0/008), and no significant relationship with organizationcommitment (P=0/102). Multivariate correlation coefficient of general physical fitness with job satisfaction (R=0.24) and explosive power (P=0/028) and endurance cardiovascular (P=0/012) can negatively predict job satisfaction. Multivariate correlation coefficient of general physical fitness with organization commitment (R=0.26) and endurancecardiovascular (P=0/007) can negatively and significantly predict organization commitment. Multivariate correlation coefficient of general physical fitness and job satisfaction with organization commitment was(R=0/54). So that, Job satisfaction can positively predict organizational commitment (P=0/0001). Multivariate correlationcoefficient of general physical fitness and organizational commitment with job satisfaction was(R=0/54). Explosive power can negatively predict (P=0/044) and organization commitment (p=0/0001) can positively and significantly predict job satisfaction. General physical fitness is inversely related with job satisfaction andorganization commitment. In multivariate regression job satisfaction and organization commitment can predict each other positively and significantly.

The goal of this research is the recognition of effective factors in the qualitative improvement of physical education course in high schools of Ghazvin city. In this research, 30 men and 39 women have been chosen by orderly random sampling. The instrumental means was the researcher-made questionnaire whose stability was obtained 0/79. Foranalyzing the data, statistical indexes have been used as well as statistical tests of Chi square, Fridmann, Mann Whitney U. The results of Fridmann Test showed that there was a significant difference in ranking of following components (p=<0/01). So that the ordinal priority are: budgetary, facilities, educational content, attitude, educational program, experimented and specialist teachers, educational goals, teaching methods, and evaluation. Also, the results of Chi Square showed that there was a significant difference among abovementioned component (P=<0/01). The results of mann Whitney Testshowed that there was not significant difference among male and female teachers. So, it can a be said that the improvement of physical education course in the schools requires further supports in order for improvement of hard ware, and soft ware appliances.

The present study aims at exploring the relationship between organizational factors (structure and technology) of Physical Education Organization of Iran with the subscales of knowledge management. Knowledge management is about sharing knowledge with others. In the past, this was often regarded as a challenge and possible reason for poor performance of elaborate KM systems (2). This investigation is of a descriptive and correlation nature which was conducted as a survey study. For data collection, a researcher-made reliable and valid questionnaire (􀄮 =.83) was applied. The total population included 261 male and female employees and managers of the Physical Education Organization in Iran. However, the final sample which was originallyequal to the main population was reduced to 233 because some of the questionnaires were not sent back to the researcher. Spearman Rank order correlation was applied for data analysis. The findings of this study show significant relationship betweenorganizational factors (structure and technology) and knowledge management subscales (knowledge creation, knowledge transition) (p<0/01). In addition, there was a negative relationship between concentration as a factor of organization structure and knowledgemanagement subscales (knowledge creation, knowledge transition) (-0/486,-0/547 & -0/385, -0/411& -0/473, -0/619). Furthermore, there was no significant relationship between ICT knowledge and knowledge creation (0/050). The results imply that in order to efficiently benefit from knowledge management, one should consider an organization as a whole, while taking and interpreting the structure and technology of an organization as important factors.

The purpose of this research is to investigate the effect of anchoring on performance and learning of asymmetric bimanual coordination. Performance and learning of asymmetric patterns of coordination are difficult. Therefore we have presented a real method of anchoring that it be applicable in real learning situation. An experimental groupincludes of 15 right-hand male students that participated in pretest, posttest and retention tests voluntarily. The task was pendular movement with right hand in 45􀋸 amplitude and circular movement with left hand that these two movements have 90􀋸 relative phase. Initially subjects participated in pretest; then they performed 200 trails during 20 tests at acquisition stage in two days. After that they participated inposttest. Finally subjects participated in retention test after two days of posttest. Results of this research indicated that t-test was significant between pretest and posttest (p<0/05), also between pretest and retention test was significant (p<0/05). The results show anchoring is an effective method for performance and learning of asymmetricbimanual pattern. Because of presentation of anchor points in real from in this research, coaches and physiotherapists can use this method for instruction of stable coordination patterns.