مجله بیومکانیک ورزشی
سال هفتم شماره 3 (پاییز 1400)

The aim of this study was to investigate the effect of a combined and core stability training program with protective measures on selected variables of physical fitness of junior and young volleyball players during the coronavirus pandemic.

15 male volleyball players [18±1.06 yrs.] after the end of the first quarantine period and then after a 12 weeks period of combined and core stability training program emphasizing on physical fitness exercises in compliance with all health protocols, as pre-test and post-test of selected key factors, performed physical fitness including lower limb strength, upper limb and abdomen endurance, as well as flexibility tests. Descriptive statistics, Shapirovik test and paired t-test were used for statistical analysis (p≤ 0.05).

The results of the present study showed that there was a statistically significant difference in the variables of upper limb and trunk muscle endurance as well as muscle flexibility, but in the lower limb strength variable, this difference was not observed in both pre-test and post-test levels.

Volleyball coaches and players can benefit from combination and core stability training with health protocols to maintain and improve fitness during the coronavirus epidemic.

 Intense training and competition lead to fatigue and muscular imbalance in wrestlers that cause postural abnormalities. Thus, it is essential to identify these changes and the related mechanisms to prevent musculoskeletal and sports injuries among wrestlers. The present study is a comprehensive review of the literature on postural changes in freestyle and Greco-Roman wrestlers.

 This paper offers a thorough review of the literature on changes in freestyle and Greco-Roman wrestlers. It encompasses a series of search queries from inception to Mar 2020 from existing databases including PubMed/MEDLINE, EBSCO Web of Science, Science Direct, Cochrane Central Register of Controlled Clinical Trials, Google Scholar, and Scopus. A host of other publications were also reviewed manually. Once candidate papers were extracted, the title and abstract were studied, those meeting the inclusion criteria were selected for further analysis, and the others were discarded. 

 A total number of 11 articles were selected. Overall, 4 articles studied postural changes in wrestlers, 2 studied Q angle and flat foot, and 5 compared the two wrestling styles.

 Results show that estimated changes in kyphosis, lordosis, forward shoulder, forward head, Q angle, and flat foot were more significant among wrestlers. However, the kyphosis angle was higher among freestyle wrestlers, while a higher lordosis angle was observed for Greco-Roman wrestlers. Moreover, a higher degree of flat foot and Q angle was observed in the dominant leg of experienced freestyle wrestlers. Results of forwarding shoulder and forward head were contradictory, and more studies need to be done.

 In a fast-paced world of technology that is changing people’s lifestyles and reducing mobility, rural women who were once a model of mobility have not been spared. This study aimed to investigate the prevalence of musculoskeletal abnormalities of the upper and lower limbs in rural women in Qazvin province.

 The present study was a descriptive-comparative study. The statistical population of this study was rural women in Qazvin province with an age range of 15-65 years and an average age (41.88±15.70). In this research, 3023 people participated and were divided into four groups with different age ranges. Subjects were selected by snowball sampling method and participated in the study voluntarily. The collection tools included consent form, musculoskeletal abnormalities registration form, caliper, vertical line, checkerboard, and New York test. Descriptive statistics were used to show the prevalence of anomalies, and the Kruskal-Wallis test was used for group comparison in SPSS software v. 24.

 Kruskal-Wallis test showed that in the variables head forward (P=0.001), torticollis (P=0.001), shoulder forward (P=0.008), uneven shoulder (P=0.001), kyphosis (P=0.001), lordosis (P=0.001), flat back (P=0.003), scoliosis (P=0.001), anterior pelvic rotation (P=0.001), genu Varum (P=0.001), genu valgum (P=0.001), genu recurvatum (P=0.001), flat foot (P=0.008), Pes cavus (P=0.004) and hallux valgus (P=0.001). There was a significant difference between groups. Also, the highest prevalence of upper limb deformities was related to uneven shoulder, head forward, and lordosis. The highest prevalence of lower limb deformities was related to anterior pelvic rotation, genu valgum, and flat foot.

 The results show that the prevalence of musculoskeletal abnormalities of the upper and lower limbs in rural women in Qazvin province is highly prevalent in the age range of 35-31 years and 50-36 years. Therefore, researchers believe that providing information about the prevalence of postural disorders can effectively design preventive programs and emphasize the need to develop corrective exercise and rehabilitation programs for this segment of society.

 Weakness in the sensory-deep receptors of the sole is one of the essential factors in lower limb movement disorders and balance in blindness. Therefore, this study aimed to compare the effect and durability of foot massage techniques on the balance of the blindness

 The present study was a one-way blind with a pretest-posttest design. The statistical sample consisted of 30 blind boys aged 20-30 years randomly divided into three groups of 10 people. The protocol of massage methods was performed on the samples for 21 days. Biodex balance system was used to evaluate the balance. The normality of the data was analyzed using the Shapiro-Wilk test. The analysis of variance with repeated measures was used to analyze the differences within the group. The ANOVA test was used to examine the differences between the groups at the significance level of 0.05.

 The results of the intra-group test showed that all three methods of foot massage improved static and dynamic balance in the blind (P<0.001). The results of the ANOVA test for comparison between groups showed no significant difference between the three methods of foot massage on static balance and posterior-anterior index of dynamic surface and internal-external index of dynamic surface (P>0.05) only on the general surface index. There is a significant difference in the dynamics of hand massage compared to the other two massages (P<0.001).

 Due to the significant effect of foot massage methods on the balance of the blind, foot massage can be used as an effective factor in strengthening the sensory receptors of the foot and ultimately improving the balance of the blind.

This study aimed to investigate the relationship between Structure profile and sports performance of the elite goalball players.

 The participants of this study were 30 goalball players competing in Iran’s men’s premium goalball league. Their anthropometric properties were measured. The performance of the players was assessed by filming and evaluating the matches. The Shapiro–Wilk test assessed the normality of data distribution. Due to the abnormality of the data distribution, the Spearman correlation coefficient test was used. 

 The results showed no significant relationship between body composition and somatotype with performance indices (P>0.05). However, significant relationships were seen between the efficiency of defense with weight (P=0.03) and body mass index (P=0.03) and also between the efficiency of penalty shots with the height of defense (P=0.005), the total length of the hand (P=0.02), and the length of two open arms (P=0.02). Furthermore, the relationships between the length of the foot and the efficiency of shots leading to the goal (P=0.009) and the efficiency of penalty shots (P=0.001) were significant. However, no significant relationship was observed between other anthropometric indices and the sports performance of the players.

 The present study results showed that despite the importance of anthropometric features, at the elite level; Experience, technique and practice and effort to improve performance in this field are much more important.

 back pain is one of the most common health problems in different societies, especially in industrialized countries. This study aimed to compare the electromyography activity of abdominal muscles and hamstrings in women with low back pain in different lifting positions. 

 The present study was a quasi-experimental and laboratory study. The statistical sample consisted of 10 women with back pain and 10 healthy women for whom using 16-channel EMG system and surface electrode, electromyography activity of the right muscles (Rectus Abdominis, Internal Abdominis, External Abdominis, and Biceps Femoris muscle and semitendinosus) while lifting with three Squat, Stoop and freestyle methods were recorded. Data analysis was performed using SPSS software. Analysis of variance was performed by repeated measures and independent t-test at a significant level (P≤0.05).

 In the stage of lifting weight, the Internal Abdominalis muscle, healthy individuals were more active in the squat technique than in Frees and Stoops, and the patients, Semitendinosus muscle was less involved in the freestyle technique than in the squat technique, but in lowering, weight Semitendinosus muscle of back-pain patients showed more activity in freestyle technique. 

 In the present study, the freestyle method in patients with back pain is safer for lifting the load than the other two methods. Also, for sports rehabilitation in people with back pain, special attention should be paid to the role and strengthening of the hamstring muscles so that the patient has better performance for lifting activities.