Showing 14 results for Performance
Masomeh Aghazadeh, ,
Volume 0, Issue 0 (11-2019)
Abstract
Improving the quality of athletes' performance and identifying the ways to optimize the performance of sports activities has always been one of the concerns of sports managers and athletes, especially in the professional and championship dimensions. With the progress of science and the revelation of the benefits of technology for human societies, sports science researchers increased their efforts to find ways to increase the optimal performance of athletes. One of the categories that has affected and transformed not only sports, but also all aspects of human life, is nanotechnology, especially nanoscience. Nanoparticles have significant effects in improving sports performance of athletes, silver and zinc oxide nanoparticles have played a role more than other nanomaterials. Therefore, this research was conducted to investigate the effect of clothes containing silver and zinc oxide nanoparticles on the sports performance of female athletes. The statistical population of the study was all women active in public sports in Maku city. The sample size was selected randomly and included 10 female athletes. The effects of treatments (sports activities with and without nano clothing) on endurance, moisture absorption, bacterial levels, high and low blood pressure, and heart rate in athletes were investigated. To determine the difference between the groups, Duncan's post-test with a probability of 0/05 was used. The results showed that the effect of silver and zinc oxide nanoparticles clothing on improving endurance of female athletes is different and increased their endurance. The effect of these clothes on the improvement of bacterial removal from the body of female athletes is different, and it increased the removal of bacteria in them. The effect of these clothes on the improvement of the blood pressure of female athletes was the same in terms of high blood pressure before training, and it did not have much effect on their high blood pressure. There was no significant difference between female athletes in terms of low blood pressure before training, and clothes containing silver and zinc oxides nanoparticles did not have much effect on their low blood pressure. There was a significant difference between female athletes in terms of high blood pressure after exercise, and clothes containing silver and zinc oxide nanoparticles were effective in reducing their high blood pressure. A significant difference was seen between female athletes in terms of low blood pressure after training and these clothes were effective in reducing their low blood pressure. The effect of clothes containing silver and zinc oxide nanoparticles on improving the heart rate of female athletes before training was not different, and it did not have much effect on their heart rate. There was a significant difference between female athletes in terms of heart rate after exercise and these clothes had an effect in reducing their heart rate. The effect of these clothes on improving the absorption of moisture in female athletes was different and it increased the absorption of moisture in them. In general, clothes containing silver and zinc oxide nanoparticles increased the sports performance of female athletes.
Student Mina Khantan, Professor Behrouz Abdoli, Professor Alireza Farsi,
Volume 0, Issue 0 (11-2019)
Abstract
Transcranial direct current stimulation (tDCS) is one of the newest supplementary method in order to improve the athletic performance and mental preparation of professional athletes. In this study, we investigated the effects of 10-session unihemispheric concurrent dual-site anodal-tDCS (a-tDCS) of the primary motor cortex (M1) and dorsolateral prefrontal cortex (DLPFC), on swimming performance, mental toughness (MT) and perceived exertion. 20 male professional swimmers (Age: 19.00±2.86 yrs) were participated in this randomized, double-blind, and sham-controlled study. 100m free-style swimming test, the sport mental toughness questionnaire (SMTQ) and rating of perceived exertion (RPE) were evaluated as pre-tests. Then, athletes received 10-session tDCS (2mA for 20 min). 48 hrs following 10th session of tDCS, evaluations were repeated. ANCOVA was used for statistical analysis. After multi sessions of tDCS, swimming performance improved significantly (P=0.03) and total MT score increased significantly (P=0.046) and no significant change was observed in RPE. Based on the results of this study, multi-session tDCS along with routine training are recommended to improve swimmers performance and psychological aspects. Therefore, tDCS might be consider as a brain conditioning method.
Phd Kia Ranjbar,
Volume 0, Issue 0 (11-2019)
Abstract
Introduction: The purpose of the present study is to introduce and examine several genes that are related to people's sports performance and can be effective in their selection and selection in their favorite sports field. Various factors of physical fitness and training ability have been investigated along with the risk of sports injury and mental fitness of athletes.
Findings: The sports performance of people and the monitoring of sports exercises have been influenced by the vast genetic map and environmental interventions. In the present study, the performance of the aerobic system with the ACE gene and its different alleles, the strength and power performance of people with the ACTN3 gene, and the risk of injury of people with different genes such as COL1A1, COL5A1, Tenascin (TNC), apolipoprotein E and blood groups were investigated. It is a prediction; also, the trainability and mental preparation of people in the talent search process can be predicted and possibly measured by genetic knowledge. On the other hand, using the knowledge of genetics and genetic profiles of athletes can be useful for detecting genetic and cellular doping and help organizations that work in the prevention of doping, such as WADA.
Conclusion: The combination of genetic knowledge and environmental interventions play an effective role not only in discussing an athlete's talent, but also in monitoring and improving their performance. While genetics can play a significant role, the prediction of sports success based on genetic knowledge has been limited to a specific set of genes. However, developing this knowledge and identifying more genes that can aid in talent identification and exercise monitoring requires further research.
, , , ,
Volume 12, Issue 7 (4-2014)
Abstract
The purpose of this study was to determine the effect of combination specific resistance and ordinary swimming training on Breaststroke swimming performance in young boys. Twenty boys of Alborz province swimming team age of 13±1 years ,weight 50/ 65±1/02kg and height 159/8 ±4/91cm, participated in this study. After the initial testing of the performance variable (Fifty-meter record of Breaststroke swimming) , technical variable (stroke number) and strength variable (strength of spinal extensor muscles), subjects were randomly divided in two groups, Experimental group (combination specific resistance and ordinary swimming training) and control group(ordinary swimming training).A week of familiarization training was performed to adapt with vest (specific resistance) and then training program were performed for 6 weeks, three sessions per week .Training program consisted of 15minutes of warmup and 8 repeats of 50 meters breaststroke with 1minute rest interval between repetitions, in exprimental group (with vest of training) and control group(without vest of training). At the end of the training, post test was performed in accordance with the conditions of the pre test. Kolmogorov –Smirnov test was used to determine normality of data distribution, Paired t-tests was used to determine within group changes and the covariance analysis was used to compare the progress of dependent variables between the two groups. The results of this study indicated that although swimming performance was significantly improved in both groups (p≤0.05) ,but there were no significant differences between the groups in fifty-meter record of Breaststroke swimming, stroke number and strength of spinal extensor muscles (p≥0.05).It may be attributed to non-professional subjects or Low-intensity resistance training.
, , , ,
Volume 12, Issue 7 (4-2014)
Abstract
Aims: This study investigated the effects of creatine and L-carnitine supplementation on anaerobic
performance and body weight changes in athletes. Methods: In this single-blind randomized clinical trial, 45
athletes were selected and randomly divided into four groups supplemented with: a) Creatine, b) L-carnitine,
c) Creatine- L- carnitine and D) placebo. The supplementation period was 28 days. Wingate anaerobic test
was done for assessing athletes' anaerobic performance and their weights were measured before and after
the supplementation period. To compare the variables before and after each test, paired t-test and anova
are used compare within and between variables respecdivey. Results: The anaerobic performance indices
in the groups receiving creatine and creatine- L-carnitine were significantly increased after intervention. Body
weights were also significantly increased in the supplemented groups. Conclusions: Based on the dosage
and duration of supplementation in this study, concurrent creatine and L-carnitine supplementation has
positive effects on anaerobic performance. Despite L-carnitine is a weight loss agent, the findings of this
study showed weight gain in the supplemented groups.
Mohammad Reza Mahmoudkhani, Hooman Minoonejad, Reza Rajabi, Amir Hossein Barati,
Volume 16, Issue 16 (12-2018)
Abstract
Judo is one of the most popular martial arts in the world. Researchers reported a higher risk of injuries during training rather than the time of competition. So, the safe and effective training methods should be considered. As development and application of injury prevention approaches and athletic performance enhancement is necessary, the purpose of this study was to investigate the effect of 8-week Judo Specific Functional Training on the injury risk factors and athletic performance in non-elite male judokas. 46 non-elite judokas participated in this study. Subjects were randomly divided into two groups of experimental (23:N) and control (23:N). For a period of 8 weeks, the experimental group attended a special judo functional training program designed by the researchers. At the same time, the control group participated in the usual judo training program presented by the coaches. The exercises were performed 3 sessions per week and 90 minutes per session. The subjects participated in pre- and post-tests. After data collection, in order to approve data normality and compare the variables, Shapiro-wilk, ANCOVA analysis was implemented at the significant level (p≤0.05) using SPSS version 21. The results showed that scores of functional movement screening (p=0.001), upper extremity Y balance test (p=0.001), vertical jump (p=0.001) and special judo fitness test (p=0.001) significantly increased among the experimental group in comparison to the Control group. This Judo specific functional training program simultaneously modifies or decreases the injury risk factors and improves the athletic performance and has more efficiency and effectiveness rather than the usual judo training program.
N Shaterkazemi, Sh Zandi, E Shirzad,
Volume 18, Issue 19 (7-2020)
Abstract
Regarding the effects of the kinematics of the movement on athletic performance and the Importance of promoting athlete’s performance on the sport fields, there is limited knowledge about the mechanism of the effect of different variables of volleyball spike. Therefore, the aim of this study was the prediction of jump performance in elite female volleyball players with selected kinematic variables. Thirty elite female volleyball players with mean age of 21.44±3.42 have volunteered for this study. Lower limbs kinematics have been recorded using 16 reflexive markers with Vicon motion analysis system during volleyball spike jump performance. Jump height and time of concentric phase of jump have been predicted by center of mas velocity during step, final step length and ranges of the motion of hip, knee and ankle with stepwise regression (α≤0.05). The results showed that knee range of motion center of mass velocity and step length could be the predictors for time of jump and center of mass velocity and hip range of motion could be the predictors for the jump height as well. Considering these results and the goal and situation of the volleyball match, the players should focus on different phases and affecting variables of the spike jump.
Amir Milan Amini, Mohamad Fashi, Rana Fayaz Milani,
Volume 18, Issue 20 (11-2020)
Abstract
This study aimed to assess the effects of acute calcium lactate supplementation intake on the performance and buffering capacity of elite amateur boxing athletes. 8 elite amateur boxers (180±4.33 cm, 24.12±3.68 years, Weight categories: -75, -64, -69, +81) were assigned to acutely receive calcium lactate (0.5 g, 80 mg calcium lactate/kg body weight) and placebo in a double-blind crossover design 90 minutes before the box competition. 90 minutes before, before competition and immediately after, blood samples were taken and lactate, PH, HCO3-, and PCO2 and also, average heart rate, and number of effective hand kick were evaluated. lactate and HCO3- significantly increased and decreased at three evaluation times in calcium lactate supplementation and placebo groups respectively (P<0.05). There was no significant difference between calcium lactate supplementation and placebo groups in lactate, pH, HCO3-, PCO2, heart rate and performance at three evaluation times (P>0.05) .Calcium lactate supplementation improves performance without significant changes in the buffering system. In other words, more effort with a similar acidity to placebo could indicate the effect of calcium lactate supplementation on the performance of amateur boxing athletes.
Effat Hosseinzadeh, Mansour Eslami,
Volume 18, Issue 20 (11-2020)
Abstract
Introduction: The ability to attain high level of speed is an essential component of success in many sports fields. However, physical qualities that underpin this ability remain unclear. The purpose of this study was to investigate the role of leg stiffness and vertical stiffness in predicting sprint running. Methods: 50 healthy females were selected among physical education students. The required kinetic and kinetic data were collected in three dimensions. The kinetic and kinematic variables rrunning skill was used to measure both stiffness variables. A multivariate regression model was used to examine the possibility of predicting running speed using leg stiffness and vertical stiffness. Findings: The results of multiple regression showed that there is a significant relationship between the two-leg stiffness and vertical stiffness with mean running speed (R = 0.671), and these two variables can predict 42% of Average speed variation (Adj. R square=0.426). Conclusion: The results of the present study showed that the ability of individuals to sprint running is likely to be significantly dependent on leg stiffness and vertical stiffness. The results of this study can provide important information for designing training programs and talent detection for trainers and specialists in this field.
Ali Molaei , Sedigheh Hosseinpour Delavar, Ghahramani Mehran, Reza Jabbari, Mohammad Jalilvand,
Volume 18, Issue 20 (11-2020)
Abstract
The present study was aimed to determine the effect of cold-water immersion and (TDCS) during the recovery period on blood lactate changes in and subsequent performance of professional male swimmers. For this purpose, 20 male participated in this study in two days with an interval of 48 hours. The two-hundred meter breaststroke was performed every day and then the subjects participated in one of the protocols, an anodic stimulation (with intensity of 2 mA)or the artificially exposed to anodic stimulation on the first day, and on the second day they were experienced the cold water immersion (12° C).The subjects' blood lactate was measured. Finally, in order to measure the effect of the investigated methods on their performance, the 200-meter swim was repeated. To analyze the data dependent t-test and analysis of covariance, LSD follow-up, analysis of variance with repeated measures, were used. The results of this study indicated that swimming performance significantly improved only in the TDCS group, with a reduction in the record time (P = 0.001). Blood lactate showed a greater decrease in the cold water immersion group (P = 0.001)
Dr Heydar Sadeghi, Mohsen Ali Darchini, Hossein Nabavi Nik,
Volume 19, Issue 22 (12-2021)
Abstract
Core stability (CS) is a popular term that has evolved into a fundamental concept the much rehabilitation, performance training and preventative programs. The purpose of this study is considering the relationship between CS power and endurance with performance of adolescence athletes. 12 male swimmers participated in the study. McGill Protocol, the core stability power, MBESTT and 30/60 sit-up test were used to measure the CS endurance and power, respectively. Participants' performance was measured as the specific (stroke-index, 100m crawl stroke) and general performance (standing-broad-jump (SBJ), vertical Jump, 9.1 m sprint, shuttle-run, flexibility and seated medicine-ball toss tests). The Pearson correlation coefficient was used to determine the relationship between the CS power and endurance with general and specific athletes' performance. The results showed only significance relationship between trunk flexion with SBJ and seated medicine-ball toss, and flexibility and total CS power score with flexibility. Also, negative significance relationship found between left lateral flexion with shuttle-run test and trunk flexion with stroke-index. The findings of this study showed a weak correlation between CS with specific and general athletes' performance. Based on our findings, there is no necessity for focusing on swimming training programs.
, , , ,
Volume 20, Issue 23 (9-2022)
Abstract
Background and Aim: Given the widespread trade in some sports, a misjudging decision can not only have huge financial consequences for competitors, but also affect the event itself. The overall purpose of this study was to determine the role of information technology and perceived organizational support on the performance of the referees of the 2018 FIFA World Cup in Russia: to investigate the mediating role of job satisfaction and self-efficacy. Methods: This is a descriptive research, correlation model, based on structural equation modeling, and its type. The statistical population of the study consisted of all referees and assistant referees present at the 2018 FIFA World Cup in Russia, of which 111 referees were 35 middle referees, 63 assistant referees and 13 video assistant referees. Results: The results showed that information technology, perceived organizational support and self-interest have a significant positive effect on the performance of the referees of the 2018 FIFA World Cup in Russia. Job satisfaction does not have a significant effect on the performance of the referees of the 2018 FIFA World Cup in Russia. Conclusion: Information technology is an effective and facilitating factor in arbitrators' decisions, so it is suggested to provide technological infrastructure in order to improve the instant decisions of arbitrators on a larger scale.
Hossein Nabavinik, Mohsen Ali Darchini, Reza Azimi,
Volume 20, Issue 23 (9-2022)
Abstract
Introduction and Objective: Core stability and plyometric exercises are training methods that athletes use to improve their performance. The purpose of this study was exploring the effect of a period of six week plyometric and core stability exercise on some of physical fitness of boy's athlete. Methods: 36 male athletes who were male with 11-14 years old participated in the semi-experimental study. They randomly divided in three group that each group has 12 subjects (first group; core stability exercise, second group; plyometric exercise and third group; control). The performance tests (standing broad Jump, Vertical Jump, 9.1 m Sprint, Shuttle Run, Flexibility and seated medicine ball toss tests) applied a day before starting core stability and plyometric exercises. Then post-test applied. In order to analysis data, ANOVA test was used (p<0.05). Results: Both core stability and plyometric exercise group showed significance increase in performance tests (Standing Broad Jump, Vertical Jump, 9.1 m Sprint, Shuttle Run). Conclusion: Based on the findings, we recommend the core stability and plyometric exercises in order to improve some of physical fitness of athletes.
Negin Gilsamaei, Dr Seyd Sadredin Shojaedin, Dr Hassan Sadeghi,
Volume 20, Issue 24 (3-2023)
Abstract
The prevalence of sports injuries in martial arts is high. Most Taekwondo injuries also occur in the lower extremities. The aim of this study is to compare the effect of a period of plyometric exercises, with and without stretching exercises, on knee valgus dynamics, flexibility and functional variables of elite female taekwondo athletes at risk of anterior cruciate ligament injuries. 45 elite female taekwondo athletes aged 15-25 years with anterior cruciate ligament injuries participated in this study. Knee valgus dynamics in squat movement were measured with KINOVEA software. Flexibility was measured with direct leg lift test and performance indicators were measured with Y-balance, three-step jump and error scoring system. The tests were conducted before and after eight weeks of plyometric exercises, along with the stretching exercises. Then, the data obtained were analyzed.There was a significant difference between the results of pre-test and post-test data measured in the two experimental groups (P ≥ 0.05). According to the stark differences based on the analyzed data, it is clearly evident that the group of athletes with plyometric exercises with stretching have obtained far superior results and outcome..Plyometric exercises with stretching had a significant effect on reducing the risk of injury, as well as increasing the flexibility and performance of elite female taekwondo athletes exposed to anterior cruciate ligament injury. Considering the vast improvements reported for the plyometric training group with stretching, it is recommended that these interventions be used to reduce the risk of injury and increase the performance of taekwondo practitioners.
