RESEARCH ON SPORT SCIENCE
Year:2006 | Volume:- | Issue:10|Papers Count:11

Purpose: Determination of anaerobic threshold using heart rate deflection point (HRDP), aiming to provide the optimal training intensity considered by sport scientist is the most important factor for coaches and athletes. Therefore, the purpose of this study was to determine the anaerobic threshold by maximum distance (Dmax) and using the HRDP.Method: Fifteen active young men (mean age±SEM = 21±1.32yrs., mean Hight±SEM = 178± 5.2CM, and mean Weight±SEM = 64.2±6.78kg) were selected as the subjects. Hoffman experimental protocol (Inital work load = 40w, Increased work load 20W/min, till to exhaustion) was used for determining heart deflection point (HRDP). During completion of protocol, Subjects heart rate was recorded every second via telemetry. At the same time, blood sampling was accomplished in five phases by angiocat and analysised for Acid Lactic concentration.Results: According to the findings of this survey, the Dmax method in determining the anaerobic threshold is an accurate method, and it was no significant differences between Dmax and lactate methods. There is high correlations between the lactate and Dmax methods (R=0.992).Conclusion: According to these results, it could be suggested that Dmax method will be an accurate and valid method for determining the anaerobic threshold, when factors affecting HRDP, applied Mathematical Model and experimental protocol were considered.There for the Dmax method could be a valid alternative of traditional, expensive, and time-consuming lactate method. Thus, coaches and athletes can use the Dmax method in anaerobic threshold determination and training intensity control.

Purpose: Exercise physiology is an important part of sport/medicine sciences, which focuses on the effect of exercise on human body performance. Many years ago it was only possible to study human body. This was along with different limitations because of difficulty in using human body tissues as experimental samples. As a matter of fact, this problem was solved by using animal model. In this model, a rodent treadmill was used to train animals. These rodent treadmills were made in other countries before, but it was expensive and difficult for us to provide one.Thus, a rodent treadmill was designed and after six pilot studies, the final version of this instrument was produced. Nowadays, more then ten samples of this treadmill are distributed by the sport science research center in universities and many research projects are done so far. The technical characteristics and functional method of this treadmill are discussed.

Purpose: The purpose of this investigation was to study the effect of progressive strength-endurance training and electrical stimulation in short time on Electronorography of suprascapular nerve in Volleyball players with infraspinatus syndrome. Method: In this study 12 Volleyball players with infraspinatus syndrome where elected, who had played Volleyball in IRAN super league with average age, height, weight, background of Volleyball activity and selection membership period in the national team (24.2±4.5 years, 192.5±1.5 cm, 86.2±6.4 kg, 8.5±4 years), 4.2±2.8 years and were devided randomly in two 6 membered groups: a progressive strength-endurance training group and an electrical stimulation group. Control group included 20 Volleyball players with average age, height, weight, background of Volleyball activity and selection membership period in the national team (25.1±4.2 years, 187.8±3.9 cm, 85.5±7.1 kg, 9±3.8 years), 3.9±2.3 years respectively without infraspinatus syndrome. We measured nerve conduction velocity of suprascapular nerve from Erb point up to the infraspinatus muscle with electronorography machine, including electrical stimulation parameters.Results: Significant increase was observed between the pre-test and post-test results in amplitude of the progressive strength-endurance training group (p<0/05) Also Significant decrease was observed between the pre-test and post-test results in latency in the electrical stimulation group. Amplitude and latency significantly differed between three groups.Conclusion: Increase of amplitude is a sign of recovery of fibers in infraspinatus muscle caused by progressive strength-endurance training, which in turn causes more strength in the muscle. Decrease in latency could happen due to relative recovery of nerve, which has responded fast to the electrical stimulation with minimum delay.

Purpose: The purpose of present study was to develop a Motor Performance scales for children aged 3-7 and determining its validity and reliability in Tehran preschool centers.Method: The methodology of this study was Descriptive - Developmental. 426 children were selected as a sample from all preschool centers at the east and west districts of Tehran. 8 Motor Performance tests for preschool aged children were chosen from available professional texts, each appropriate for assessing one of physical abilities and movement patterns. The tests were: Vertical jump, Distance jump, Ball catching, Precision of throwing, Throwing distance, Balance, Kicking and 18 meter dash (not administered due to space limitation). Content validity was investigated with comments of 10motor development experts. Pilot studies were conducted on 30 children and any modification and appropriateness as well as practical aspects of the scales, were verified. The modified test battery then, were administered on samples. To determine validity coefficient the score differences between aged children were computed using analyze of variance (Allen, 1976). Reliability was analyzed on 30 persons using test-retest Pearson correlation coefficient.Also, the trend of children's Motor Performances and Gender differences were observed and normtable for each test using descriptive statistics was provided.Results: The results demonstrated that the seven tests have high reliability and content validity. Relative findings to gender showed that there was a significant difference between boys and girls in all of the tests, except in Ball catching and Balance tests. Conclusion: The researchers or educators can use tests for evaluating and measuring motor performances among preschool children.

Purpose: The purpose of this study was to examine the readiness of enterpreneurs in physical enducation university students.Methods: 75 voluntary students (M=24/23, SD=3.01) completed the entrepreneur readiness questioner (ERQ).Results: Chi square test results indicated that there was no significant relationship between entrepreneurs in sport and sex. Descriptive statistics results showed that 50 percent of students were ready for enterpreneuringin sport in the next five years, 43.3 percent believed that their readiness for enterpreneuringin sport is moderate and 40.5 percent believed their information isn't sufficient for becoming entrepreneurs in sport and they must learn more.

Purpose: The purpose of this research is finding the relationship between organizational commitment and burnout among instructors of physical education general courses of Azad Islamic Universities of IRAN.Method: The method of this study is correlative. The sampling frame for this study consists of instructors who teach Physical Education in general courses 1 and 2, teaching in Azad Islamic Universities of IRAN. Systematic random samples which includes of 212 faculty and 187 invited teachers received mailed questionnaires. The measuring instruments were demographic information questionnaires and Maslach, Burnout, Meyer and Allen organizational commitment questionnaires. In this study descriptive statistics was for organizing, summarizing, customizing and describing data. Significant mean differences were computed by T-Test method. Pearson’s coefficient is used for finding relations. Zr Fisher was used to find whether the difference relation coefficient among variable parts was significant or not. Results: Findings of this research showed the significant relationship between frequencies and tenses of depersonalization and emotional commitment were observed in faculty board members. There were significant relationship between frequencies of depersonalization and emotional and normative commitment and also its tense of affective commitment among invited teachers. There were significant relationship between emotional commitment and emotional exhaustion frequency and also emotional commitment and tense of depersonalization along invited instructors. Conclusion: Results shows that organizational commitment and burnout in full time faculty are more than invited instructors. Only emotional commitment can predict the burnout (depersonalization) in these instructors.

The Aim of this research was to find the effectiveness of flexibility and Plyometric sport-treatment methods in improving the kyphosis among 6th grade male school students in Ahwas. The samples of this study which includes 90 students (mean and standard diviation of subject's age was, x=12/81, and SD=0/75) were selected randomly and put into three groups: Two experimental groups and one control group. The results of this study showed that Flexibility and Plyometric Exercises were effectiveness in correction of Kyphosis in subjects (p<0/001). However, there was no significant differences between Flexibility and Plyometric Exercises in correction of Kyphosis at (p<0/05). According to the findings of this research, Practicing Flexibility and Plyometric Exercises are useful in correction of Kyphosis.

Purpose: The aim of this study was to assess and compare resources of control and feeling of loneliness in athletes and non-athletes female student.Method: One hundred Basketball players and one hundred non-athletes with the same age (17.41±0.56) female students, participated in this study. UCLA and levenson questionnaires were used for gathering data. Spearman correlation coefficient and Mannwithness U were applied to analyze the data.Results: Significant differences in sense of loneliness between athletes and non-athletes were observed, and meaningful correlation showed the tendency to chance (external control) and loneliness in both group.Conclusion: Results confirms Psych-social benefit of physical activity. People with tendency to external control (chance) in their life, experience more loneliness.