Showing 5 results for razi
Dr Nohamadjavad Razi, Hasan Modares, Zahra Shakeri Hosinabad,
Volume 0, Issue 0 (11-2019)
Abstract
The aim of this study was to investigate the effect of virtual education conditions and increasing sitting time on musculoskeletal status and physical activity of students during the corona pandemic. In the present study, standard Nordic musculoskeletal status and Beck physical activity questionnaires were used. The statistical population of the present study included male and female students of Farhangian University of Yazd Campus, of which 450 people participated in the present study as a sample. McNemar's, Mann–Whitney U and Spearman correlation tests were used at the significance level of P≤0.05. There was a significant difference between the prevalence of musculoskeletal disorders in the neck, shoulders, back, and waist before and during the coronavirus pandemic (P≤ 0.05). There was a significant relationship between physical activity and musculoskeletal disorders (p <0.05). There was a significant relationship between Internet Time usage and musculoskeletal disorders (p <0.05). Musculoskeletal disorders in students who did not follow the sitting pattern, in the neck (p <0.0001), shoulder (p = 0.006), wrist (p = 0.002), waist (p = 0.001) pelvis (P = 0.01) and knee (p = 0.001) were significant. The corona epidemic and the quarantine conditions may have adverse effects on the musculoskeletal condition of students, and prolonged sitting and non-observance of the principles of sitting aggravates these factors.
Morteza Hoseini, Dr Heydar Sadeghi, Dr Razieh Yousefian Molla,
Volume 0, Issue 0 (11-2019)
Abstract
Background and purpose: Determining specific abilities and skills in volleyball players depends on the amount of anthropometric, physiological, biomechanics and psychological characteristics of the players in this field and is vital for improving the performance of sports skills in them. Since by comparing these important factors in the group of teenagers and young adults, it is possible to guide teenagers towards success factors in youth and adulthood, the purpose of this research was to compare the main characteristics of elite teenage and young male volleyball players.
Methods: 30 male members of the national youth volleyball team of the Islamic Republic of Iran (15 youths and 15 teenagers) were examined in terms of their main anthropometric, biomechanics, physiological and psychological characteristics with the aim of evaluating and determining the main components and comparing them. In order to determine he main components of the evaluated indicators, first the PCA statistical method and then the independent t statistical method were used to compare the two groups(0.05≥p).
Results: Among the main indices of anthropometric, biomechanical, physiological and psychological characteristics, only the physiological index of maximum heart rate showed a significant difference between the two groups (0.05≥p).
Conclusion: It seems that the main differences of volleyball players in these two age groups are more related to experience in the game and mastery in the implementation of various skills and techniques, and all these main features can be found in the talent search process of this group of young people.
Razie Yaqoubi, Heydar Sadeghi, Ali Yaqoubi,
Volume 16, Issue 15 (9-2018)
Abstract
Since the anthropometric and biomechanical parameters role is effective in improving the quality of sports skills, researchers and sports scientists are interesting to identify and communicate between these factors. The purpose of this study was making relationship between some of anthropometrical and biomechanical parameter of girl swimmers in swimming breast strokes. Twenty girl Swimmers (mean±SD: age 12±2 years; heights 147.50±11.23 cm; weights 39.53±9.58 kg) performed in this study. After compeletting the personal and satisfaction form anthropometric charactrastics, motion domain, power swimmer’s record along with information about the number of arm and leg kicks in distance of 25 meters was measured. Descriptive statics (mean, Standard deviation) and deductive statics (pearson corrolation, principle component analysis (PCA) to the determine the main parameters influencing and multiple regression to determine the role of main parameters selected) were used for data analysis. Results indicate the relationship between weight and length with swimmers stroke length in swimming breast stroke. Also there was a relationship between body type (endo morph, mezzo morph) with some of swimmers biomechanical parameters (speed, number of legs kicks, top power, hyper extension, motion domin of thigh). The given results indicate that there was a relationship between percentage of the anthropometric and biomechanical parameters in swimmers, and some of biomechanical parameters predictors of back and front crawl swimming in the same swimmer were different.
M Termeh, A Ghanbarzadeh, M.h Honarvar, K Heidari Shirazi,
Volume 18, Issue 19 (7-2020)
Abstract
In a walking cycle design, maximizing the upright balance should be considered in addition to the kinematic constraints, energy consumption rate must be considered. The purpose of this study is to find the optimal step length obtained for each person according to the physical features. In this research, in order to minimize energy consumption rate by considering maximum balance two cost function were defined. the fall cost function was designed based on the concept of MOS and balance index. To investigate the upright balance and to reconstruct the movement pattern, Data from normal walking gait of healthy subjects was taken and seven links model was defined. In this study, the optimal step length was obtained for the person with height, weight and gait cycle characteristics. it is shown that for a person of 92kg mass and 1.87 meters height, the best step length in walking would be 0.54 meters. In this study, the kinematic and kinetic characteristics of human motion were identified by the analysis of gait patterns on a treadmill. Through the calculation of the balance index, individuals are helped to find the optimal step length for which the maximum balance is achieved. The results of the study can provide the optimal step length to correct the gait pattern.
Mohsen Mohammadnia Ahmadi, Razieh Heidari,
Volume 21, Issue 26 (12-2023)
Abstract
Nowadays, the use of traditional herbal remedies for the prevention and treatment of diseases along with exercise has become very popular. The aim of this study was to investigate acute effect of hydro alcoholic extract of melissa officinalis on metabolic rate, substrate oxidation and salivary cortisol during and after high-intensity interval exercise (HIIE) in inactive women. Ten inactive women were selected based on criteria (BMI 22.28±0.60 kg/m2). Individuals participated in two separate sessions. In the first session, extract of melissa officinalis (500 mg) were intake one hour before HIIE. In the second session, the placebo (500 mg of starch) was intake. The HIIE program consisted of 11 alternates (1-minute with 90% vVO2max followed by 2-minute rest intervals with 60% vVO2max). Pre, during and after HIIE, respiratory gases was measured using the respiratory gas analyzer and was used to calculate metabolic rate (Energy Expenditure, VO2) and substrate oxidation (Fat oxidation, Respiratory Exchange Ratio (RER)). Heart rate monitored by polar sensor. Salivary cortisol after collection was measured by chemiluminescence method. Based on results, there was no significant difference in VO2 (P =0.51), Fat Oxidation (P= 0.9), RER (P= 0.76), Heart rate (P= 0.42) and energy expenditure (P=0.6) between melissa officinalis and placebo intake. Also, there was no significant difference in salivary cortisol (P= 0.15). Generally, hydro alcoholic extract of melissa officinalis supplement intake along HIIE has no effect on metabolic rate, substrate oxidation and cortisol level in inactive women.
