درخت حوزه‌های تخصصی

Shooters typically make great efforts to strengthen their physical and motor abilities, but are often less aware of the cognitive and psychological factors that affect their performance and skill performance. Therefore, it seems that shooters, especially novice shooters, are not very familiar with the mental skills related to shooting and pay less attention to mental training. However, cognitive training has recently been recognized as one of the basic skills required in perceptual-motor activities. The present study was conducted to determine the effect of training cognitive imaging strategies versus training of motor representation strategies on the acquisition and retention of shooting skills. This randomized controlled clinical trial study was performed on 45 undergraduate military science students with an age limit of 18 to 25 years, studying in the second semester of 1997-98. Subjects were randomly selected from a university of military sciences in Tehran and randomly divided into three groups of mental imagery, motor representation and control using a table of random numbers. The intervention groups received a three-week mental imagery training program, motor representation along with shooting training (five sessions per week). The control group only participated in shooting training. In order to evaluate the performance of shooters in the pre-test, post-test and memorization stages, a SCAT machine was used. Statistical analysis was performed using SPSS20 software and p value less than 0.05 was considered significant. The results of combined analysis of variance showed that both cognitive imaging and motor representation interventions had a significant effect on improving the record of novice military shooters (P≤0.05). The results showed that although there was no significant difference between motor representation and cognitive imaging groups in the post-test stage, however, a significant difference was observed between the motor representation and cognitive imaging groups (P = 0.006) in the retention stage. The results show that cognitive imagery and motor representation interventions can improve the performance of novice military shooters, although motor representation is more likely to be effective than cognitive imagery

Purpose:  Prophylactic effect of PNF stretching is performed with an expectation to reduce the risk of eccentric exercise-induced muscle damage and enhance drop jump performance.The purpose of this study was to examine the effects of proprioceptive neuromuscular facilitation stretching combined with plyometric training on deep jump in non-athlete male students. Method: The study design was a single blinded, randomized, concurrent parallel trial. Forty-two non-athlete male students were volunteered to participate in this study. Participants were assigned into plyometric (n=21) and plyometric & PNF (n=21) groups. Maximum and minimum vertical displacements, flight time, joint power, maximum landing force, peak take off instantaneous velocity were measured at baseline and 48 hours following the plyometric exercise protocol. A Vicon (200 Hz) motion analysis system with six T-Series cameras and two Kistler force plates (1000 HZ) were used to record kinematic and kinetic data, respectively. A two-way repeatedmeasure ANOVA (group x DOMS) was used to analyze data. Results: There was a significant difference between the pretest and the posttest scores in the intervention group for maximum vertical displacement (p=0.028), flight time (p=0.042), and Power average (p=0.026). Conclusions: This prophylactic treatment on mechanical parameters of deep jump during timing was useful. Eventually, results suggest that preventative treatments can have a significant effect on maintenance functional parameters or even helping to slow exercise-induced muscle damage for alleviating its symptoms.

Infertility is a health problem that affects about 10-15% of couples worldwide. Infertility is defined as the inability of couples to successfully conceive a child after one year of unprotected sex. The causes of infertility are often not easily identified. However, this disorder appears to be due to genetic or environmental factors, some of which may be modifiable and may be considered as a treatment option. The use of emerging infertility treatment technologies has been somewhat effective. However, these methods are very expensive and, in some cases, their success rate is relatively low. A sedentary lifestyle can lead to several disorders such as cardiovascular diseases, diabetes, cancer and conditions such as obesity. Obesity can have a negative effect on the fertility of couples. Overall, it seems that changing the sedentary lifestyle and increasing physical activity by performing regular exercise training can enhance the chances of fertility. However, it should be noted that strenuous exercise training has a negative effect on fertility.