مجله بیومکانیک ورزشی
سال پنجم شماره 1 (بهار 1398)

The purpose of the present study was to investigate the relation between core stability muscle’s endurance and static balance with shooting performance of military soldiers.

One hundred participants of the military training course (age 23/92±1/66 years and weight 73/96±12/77 kg) participated in this study. The shooting test was performed by the subjects and divided them into two groups with high and lower shooting scores of 60. Endurance of core stability muscle and static balance measured by core stability exercise and stork test, respectively. Pearson's correlation test and independent-T test were used to analyze data with significant level of 0/05.

Test results showed a significant correlation between shooting scores and core stability muscle endurance (P=0/000, R= 0/661), shooting scores and static balance (P=0/000, R= 0/684), and static balance with core stability muscle endurance (P=0/000, R= 0/718). The independent t-test also showed a significant difference in the core stability muscle endurance and static balance of subjects in two groups (P=0.000).

Endurance of core stabilator muscles enhance the balance, and these two factors improve shooting performance. Therefore, it is recommended that these exercises be included in the shooters' physical fitness program.

Deafness, in spite of the damage to the relationship, is also associated with other physical disorders such as imbalance and cognitive impairment. The study of balance and cognitive function in deaf has been considered by researchers in a few studies, but the relationship between these two functions has been less relevant. The purpose of this study was to examine the relationship between attentional function and balance performance in deaf people.

39 deaf students from exceptional schools in Hamadan and 40 healthy students participated in this study. The Information about attentional performance of the subjects was evaluated by Flanker, continuous performance and Stroop softwares. Also, the balance was assessed using the balance subset of the Bruininks-Oseretsky Test of Motor Proficiency-II, a standardized test of static and dynamic balance. Data were analyzed using Maan-Withney U, Wilcoxon and Spearman test statistical methods. Results were analyzed by SPSS software with p < 0.05.

The results showed that deaf people have significantly lower balance and cognitive function than healthy subjects. The results of correlation test showed that the highest correlation was observed in Flanker test with heel-toe walking test (P <0.05).

Depending on the results presented in this study, deaf people have a greater dependence on visual information. It may also be possible to improve motor function by increasing the amount of attention.

The aim of this study was to evaluate the muscular activity timing during running in male children with forward head posture compared to healthy control ones.

12 healthy male children with forward head posture (age: 11.7±1.4 years; height: 149.7±6.2 cm; Mass: 38.0±4.7 kg) and 16 healthy male children (age: 11.8±1.5 years; height: 148.2±6.6 cm; mass: 39.6±0.4 kg) were volunteered to participate in this study. The timing of muscular activity for erector spinae (cervical region), sternocleidomastoid, serratus anterior, upper and lower trapezius muscles of both right and left sides were evaluated during barefoot running. Muscular activity was recorded with a 16-chanels electromyography system. Independent sample t-test was used for statistical analysis.

Finding did not demonstrate any significant differences in onset and offset of muscular activity during walking between both groups (P>0.05). The time duration of right erector spinae muscle in the healthy group was greater than that forward head group about 41 ms (P=0.024). Also, the time duration of left sternocleidomasteoid in the healthy group was longer than that in the forward head group by 64 ms (P=0.037).

In sum, these results could be used in rehabilitation protocols for children with forward head posture in clinical settings.

The aim of this research was making comparison between landing
kinematics parameters at different minutes of simulated soccer game

15 soccer players from youth team of Sanay Mes of kerman voluntarily participated in this study who had records (2 years) in Premier League of Iran. They were at age (17.551.12) and weight (62.217.22). The players did Bangsbo fatigue protocol, which, is simulated a soccer game; Then, every 15 minutes players performed 2 counter movement jump, and we compared landing kinematics parameters. Performances were recorded with 3 cameras, 120 HTZ (Sony A7S). Information extracted from kinovea, and repeated measures were used for data analysis.

  the result showed  significant differences between players knee flexion at landing at minute 0 and minute 60 with other durations (P<0.05), and there are significant differences between dominant leg knee valgus at minute 0 , 60 and 105 with other durations. No differences show between in non dominant leg knee valgus at different minutes of game.

Results show minutes 0, 60 and 105 of a simulated soccer game are dangerous time for ACL injury in landing task. Also it is obvious biomechanics of dominant leg in landing task has more change than non dominant leg. Furthermore ACL injury in dominant leg is more than non dominant leg.

Due to the repeated of wrestling and a relatively high percentage of injuries in this sport Identify ways of preventing the damage of the utmost importance. The present study investigates the effect of eight weeks of selected Thera-band's exercises on the balance and functional movement of adolescent wrestlers in the city of Baft.

The subjects of this study included 30 athlete men wrestlers, who were selected randomly and divided into two groups of exercises (age: 17.27, height: 1.72 m, weight: 71.53 kg and body mass index: 24.01) and the and controls (age: 17.07 years, height: 1.74 meters, weight: 72.46 kg, and body mass index: 23.88). A questionnaire was used to collect demographic information and about the history of sport, and to measure static and dynamic balance and functional movement respectively, stork test, Y balance tests and functional movement screen test were used. Independent and correlated t-test, Yu-Mann-Whitney and Wilcoxon tests were used to compare mean differences with P-value of 0.05.

The results of the study showed that there is a significant difference between the static balance (p <0.001) and the total dynamic balance (p <0.001) between the two groups,

Pay attention to the results it seems that running a low-cost program can be effective in improving balance and performance. According to the results it seems that athletes in the field of sports along with professional training wrestling and free weights use the training with Thera-band's to improve the motor pattern to reduce the amount of damage and improve their movement patterns.

Characterized the musculoskeletal abnormalities to any tissue damage of the musculoskeletal system and nerves which disrupts function of the limb, So the purpose of this study was the comparison of musculoskeletal abnormalities of the upper trunk in freestyle wrestlers with greco roman  and chokheh wrestlers.

 This descriptive-analytical study was carried out on 15 freestyle wrestlers, 15 greco roman wrestlers and  15 chokheh wrestlers in north khorasan province during 2019 year. Selected subjects were purposefully from available community. Kyphosis and lordosis angles evaluation was performed by using flexible ruler. Evaluation of forward head and forward shoulders perform from side view with digital cameras and angles analyzed by AutoCAD software. For data analysis, was used ANOVA test and Shafa's follow-up test.

Determined according to the results, in all musculoskeletal abnormalities of the upper trunk, other than lumbar lordosis, freestyle wrestlers had a higher percentage of abnormalities than greco roman and chokheh wrestlers (P<0/05), Lumbar lordosis was higher in greco roman wrestlers to compared freestyle and chokheh wrestlers (P<0/05).

According to the research findings, it can be concluded that abnormalities in the head, shoulders and spine areas, can be affected by the type of sport and Maintaining an inappropriate posture for a long time is also a factor in the development of musculoskeletal abnormalities.