[Upper quarter functional stability in female volleyball players with and without anterior shoulder instability, with consideration of arm dominance]

Objective: The aim of this study was the comparison of the functional stability of dominant and non-dominant shoulder in female volleyball players with and without anterior shoulder instability, using YBT-UQ

Materials and Methods: In this descriptive study, 28 female university volleyball players [age=20 to 25 years] were categorized into healthy [n=14] and anterior shoulder instability [n=14] group. Upper quarter y balance test [YBT-UQ] was used for measuring functional stability of both dominant and non-dominant shoulder. After checking the normal distribution of the results with 1-s Kolmogorov-Smirnov, paired sample t-test and independent sample t-test were used for comparing the dominant and non-dominant shoulder's functional stability and for comparing the results between groups, respectively

Results: Higher YBT-UQ composite score was observed in non-dominant shoulder and dominant shoulder of the healthy group and the non-dominant shoulder and dominant [injured] shoulder of shoulder instability group, respectively. No significant difference was observed between functional stability of both shoulders of the healthy group [P=0.144], while the functional stability of the non-dominant shoulders of the instability group was significantly higher than the dominant unstable shoulders [P=0.001]. The results of functional stability of the unstable shoulders of the injured group were significantly lower than the results of the dominant shoulders of the healthy group, while in non-dominant side, all directions but the Superolateral direction showed significant difference

Conclusion: Based on the results of this study, functional stability of the unstable shoulder of female university volleyball players is lower than the functional stability of their non-dominant side or the functional stability of the healthy subjects; Therefore, we suggest that the upper extremity stabilization exercises, specially the closed kinetic chain exercises should be added to the shoulder rehabilitation programs

[The comparison of the amount of EMG activity of the selected involved muscles in hip strategy in female athletes while standing on one leg on shuttle balance and wobble board]

Background and Aim: Use of shuttle balance which has recently been produced in Iran seems to be beneficial in exercise programs for prevention of sports injuries and facilitating recovery. The purpose of this study was to compare the amount of the electromyography activity of the muscles involved in hip strategy while standing on one leg on shuttle balance and wobble board

Material and Methods: In this comparative study we measured the amount of EMG activity of selected muscles [rectus femoris, hamstring, rectus abdominis and erector spine, as the most important involved muscles in hip strategy], in 15 female students of faculty of physical activity and sport sciences of Tehran university by surface electromyography during standing on one leg on shuttle balance and wobble board. The findings were compared using multivariate variance analysis

Results: The results showed a significant difference between shuttle balance and wobble board in regard to the amount of EMG activity of involved muscles in hip strategy[P=0.001]. Also the results showed that the rectus abdominis muscle on wobble board and the rectus femoris and hamstring muscles on shuttle balance had significantly more electromyography activity [P<0.05]. There was no significant difference in erector spine EMG activity between the two devices [P>0.05]

Conclusion: It seems that standing on shuttle balance can lead to higher electromyography activity in the muscles of knee joint [rectus femoris and hamstring]. So we recommend use of shuttle balance in balance training programs

[Effect of feedback corrective exercise on knee valgus and electromyographic activity of lower limb muscles in single leg squat]

Objective: The aim of this study was assessing the effect of feedback correcting exercise in front of mirror during running on frontal plane knee and pelvic kinematic and electromyography activity of some lower extremity muscles in single leg squat [SLS]

Materials and Methods: This study was quasi experimental. 23 active female subjects participated in two experimental and control groups with mean age [21.86+/- 2.43] years .experimental group contains subjects with knee valgus and pelvic drop angle more than a mean plus one standard deviation of the population in functional SLS. Muscular activity [RMS] of gluteus maximus, Gluteus medius, rectus femoris, vastus medialis, vastus lateralis, biceps femoris and semitendinosus, angle of knee valgus and pelvic drop were register in end of SLS Pre and post of 8 training sessions. Comparing Variable has done with independent t statistical test between 2 groups and pair sample t test within each groups with significant level of 0.05

Results: Statistical analysis Before training showed no significant differences in pelvic drop between two groups [P and ge0.05], but knee valgus angle was significantly more than control group [Pandle0.05]. In spit that most muscle activities [% MVC] except biceps femoris [Pandle0.05], were greater in experimental group, no significant difference [Pandge0.05] has seen in two groups. Comparing pre and post test has showed no significant difference in knee valgus of experimental group, however it decreased around 2 degrees and although%MVC decreased in all muscles, just rectuse femoris has shown significant difference [Pandle0.05]. No significant difference has seen in control group in all variables [Pandge0.05]

Conclusion: Findings showed poor neuromuscular control in experimental group which improved to some extent after training because lower muscle activity and energy consumption in specific movement with similar kinematic indicate improvement of motor control or cause learning. It seems that mirror corrective exercise is responsible of learning by activating mirror neurons. Also decreasing muscular activity in movements cause decreasing fatigue, so possibility of injury may decrease, regarding the relation between fatigue and most injuries. Although there is some evidence that this training may cause positive changes in knee valgus and lower limb neuromuscular activity but more researches are needed to reach certain results

Acute effect of static stretching of quadriceps, hamstrings and gastrocnemius muscles on knee joint position sense in football players

Purpose: Everything that impairs joint proprioception system can harm joints. It has been stated that stretching exercises can change properties of the proprioceptive receptors and as a result changes the sensibility of the joints proprioception. Due to fact that static stretching has greater use between athletes, it is necessary to give useful information about the safety of these stretching exercises and their effect on knee joint position sense. Therefore, the purpose of this study was to determine the effect of static stretching of selected muscles around knee on knee joint position sense in football players

Methods: This study was a quasi-experimental research with pretest and posttest design. In this study, 30 soccer players at the college level, with the mean age of 23.20 +/- 1.45 years were selected through purposeful sampling. Before performing stretching exercises and measuring, subjects had 5 minutes warm up on a fixed bike with the same speed. Then, knee joint position sense were measured by electrogoniometer SG150 model and the achieved figures were recorded as pretest record in the record sheet. Then static stretching exercise protocol was applied on the selected muscle and immediately after that, joint position sense was measured. The obtained data were recorded as posttest record. The paired t test was used to compare the mean of pretest to the posttest mean

Results: The results of the study showed that there is no significant difference between the mean of knee joint position sense before doing static stretching exercises and thereafter [P = 0.13]

Conclusion: According to the results of this study, athletes, trainers and coaches can use the static stretching without fear of negative effects on the proprioception

Comparison of the forward head posture on scapular muscle contributions during shoulder flexion of predominant arm in women with forward head posture

Because of the corrigibility of forward head posture [FHP], the recognition of the relationship between this deformity and scapular rotator muscles may be influential on scapular muscle activities in detection of better way to improve movement disorders. Therefore, the aim of this study was to compare the serratus anterior, upper and lower trapezius muscle contributions during shoulder flexion without weight in women with and without FHP. In this case-control study was carried out on 18 women with FHP and 14 healthy subjects who were matched. EMG muscle activities were recorded during shoulder flexion and abduction. The value of each muscle divided on total muscle values to calculate contribution ratio and independent t-test was used to compare contributions between groups. There was a significant decrease in serratus anterior muscle activity ratio [p=0.002] and a significant increase in upper trapezius muscle activity ratio [p=0.001] between subjects with and without FHP. There was not also significant difference in contribution of lower trapezius muscle. Contribution of the serratus anterior muscle in individuals with forward head posture is less than healthy subjects. The contribution of upper trapezius muscle also in individuals with FHP is greater than healthy subjects

[Clinical and radiological assessment of anterior cervical discectomy]

Cervical discectomy has a high success rate. This study aimed to evaluate clinical and radiological results of anterior cervical discectomy. This was a retrospective study in which its emphasis was on surgical outcomes in patients operated with anterior fusion surgery method along with artificial cage. The study was conducted on 43 patients who underwent standard Smith-Robinson technique. Postoperative follow-up period was 2 years. Clinical assessment was done through Odom criteria, Neck disability index and VAS. The mean age of patients was 50 y. The most common symptom was neck pain and sensory disorder was the most prevalent sign. The most common level involved was C5-6. The mean medical treatment period was 4.5 months. Motor defect and neck pain were the main reasons of surgery. According to Odom Criteria, 80% of patients had reasonable satisfaction after surgery. Also, on the basis of neck disability index and visual analog scale of neck and associated pain, patients had significant improvement. The rate of successful fusion was 95%. Due to the possibility of complete discectomy and complete removal of compression, anterior surgery approach is preferred over the posterior one.

Exercise effects on risk of cardiovascular disease among Iranian women

Physical inactivity is more prevalent among women than men, varies by ethnic groups, and becomes increasingly prevalent with age. The aim of this study was to examine the effects of a 12-week exercise program on the cardiovascular disease risk and fitness of Iranian middle aged women. This was a randomized controlled trial study. Participants in the training group [n=20] performed treadmill running exercise at a high intensity [70-80% of maximum heart rate, 0% grade] for 30 min/day, 3 days/week. On the other hand, participants in the control group [n=20] were asked to maintain their habitual lifestyle and not change their activity or dietary habits. Measurements of body mass index, waist/hip ratio, blood pressure, total cholesterol, and lipoprotein subtractions were taken before program and after 12 weeks. Changes in 10-year risk scores for coronary heart disease were calculated using Framingham risk equation. Significant decreases in systolic and diastolic blood pressure, reduction in 10-year risk of coronary heart disease, and reduction in lipid levels were found within the training group between baseline and 12-week measurements. No changes were found in these parameters within the control group. The study provides evidence for the positive effects of exercise training on the reduction of cardiovascular disease risks among women aged 40-55 years

Effects of consecutive supervised core stability training on pain and disability in women with nonspecific chronic low back pain

Low back pain is a very common health care problem affecting 85% of population. Spine rehabilitation programs are very various in subjects with chronic low back pain but core stability training is often the chosen treatment. However, the aim of this study was to examine the effects of consecutive supervised core stability training on pain intensity and disability of nonspecific chronic low back pain. Twenty-four non-athletic females with chronic low back pain were participated in the study. They were randomly divided into two groups: experimental group [12 days consecutively under physical therapist supervision] and control group [no intervention]. The subjects in both groups were not allowed to perform any sport activity during 12 days of study. Before and after the intervention, visual analogue scale and the ososetry disability index were used to assess pain intensity and disability, respectively. The findings show that the disability and intensity pain variables were significantly decreased in the experimental group [P=0.0001 and P=0.003, respectively], while no significant changes were found with respect to those variables in the control group. Consecutive supervised core stability training may decrease the pain intensity and disability of the patients with chronic low back pain