نشریه مطالعات طب ورزشی
پیاپی 14 (پاییز و زمستان 1392)

The purpose of this study was to investigate the scapulohumeral rhythm and isometric strength ratio of shoulder agonist to antagonist muscles in handball players and non-athletes. 40 subjects (20 handball players، age: 22. 21±2. 1 years، and 20 non-athletes، age: 22. 21±2. 3 years) volunteered for this study. Manual Muscle Test (MMT) was used to measure isometric strength of shoulder muscles and two inclinometers were used to measure humeral and scapula range of motion. Scapulohumeral rhythm was calculated from division humeral elevation to upward rotation of the scapula at 45°، 90°، and 135°، from 45° to 90° and from 90° to 135° abduction in frontal plane. There is no significant difference in ratio of agonist to antagonist muscles between dominant and non-dominant shoulder in non-athletes; while there is significant difference in ratio of abductor to adductor muscles (p=0. 002) between dominant and non-dominant shoulder in handball players. Also، there is no significant difference in scapulohumeral rhythm at different angles of abduction between dominant and non-dominant shoulder in non-athletes while there is significant difference in scapulohumeral rhythm at 90° (p=0. 01)، 135° (p=0. 02) and from 45° to 90° abduction (p=0. 02) between dominant and non-dominant shoulder. We suggest shoulder muscles balance (abductor to adductor especially) in dominant shoulder of overhead throwers that perform their activities unilaterally for prevention of perturbation of scapulohumeral rhythm.

Change in the proper alignment of head on the body and subsequently in the cervical and glenohumeral joints is one of the risk factors reported in the previous studies. The purpose of this study was to investigate the influence of a 12-week corrective exercises program on forward head (FH) and forward shoulder (FSh) deformities. Forty subjects (20 males، 20 females) with excessive FH (>46º) and FSh (>52º) angles were chosen as samples using purposive sampling method. The average of age، weight and height of the samples were 21. 08±1. 67 years، 63. 23±12. 70 kg، and 170. 21±10. 21 cm respectively. The subjects were randomly divided into two groups of 20 experimental and control groups. Photogrammetric method technique was used to measure the angles of the FH and FSh. Data were analyzed using descriptive and comparative (Paired sample t test) statistical methods. The results demonstrated a significant decrease in the angles of forward head and shoulder in the experimental group. Also، the Cohen’s effect size of the exercise program was “large”. Therefore، using this program is recommended in subjects with these deformities.

Parkinson’s Disease (PD) is a progressive neurologic disorder in older age groups، which affects the central nervous system. The disease creates disruption in the basal ganglia of the brain; therefore the patient makes a lot of movement problems. The purpose of this study was to investigate the effect of combined training (balance and resistance) on balance، flexibility and motor function of PD patients. Twenty-two subjects with PD from Isfahan selected and randomly assigned into an intervention (N=11) and control groups (N=11). Patients in experimental group participated in a training program for 10 weeks. Before and after the training program static balance (opened and closed eyes)، flexibility (sit and reach test)، and motor function (with UPDRS) of all patients were assessed. The data were analyzed using independent and dependent t-test. In the experimental group patients، balance (both dominant and non-dominant legs، both opened and closed eyes)، flexibility and motor function were significantly improved after intervention program (P<0. 05). Furthermore، significant differences were found between groups in all variables (P<0. 05). It can be concluded that resistance and balance training program improves balance، flexibility and motor function in PD، therefore، it can be recommended as a modality for these patients.

The aim of the present study was to examine the difference between maximum effort low drive and high drive soccer instep kick in kinetic parameters by developing dynamic model. Six skilled collegiate soccer players volunteered as subjects in the study. Average of the subjects individual characteristic have contained، age: 25/16±2/2 years، weight: 70/6±6/6 Kg and height: 173±6/5 cm. In order to calculate the lower extremity joints kinematic parameters and kicks velocity، five markers attached to anatomical points of the foot (iliac crest، greater trochanter of femur، lateral epicondyle of knee، lateral malleolus and lateral phalanges of foot) and their movements were filmed at 240 Hz with two Casio ZR200 cameras. In order to calculate kinetic parameters of motion، kinematic parameters were entered into the model. This model was built with Simmechanics software and it had 4 degree of freedom. The results indicate that there were significant difference between low drive and high drive instep kick in thigh flexion and ankle plantar flexion moment. Also no significant different were found in thigh abduction and knee extension moment among low drive and high drive kicks. Finally، to demonstrate a powerful and coordinate soccer instep kick، joint torque should occur with a sequence.

Functional ankle instability is the most common residual and debilitating symptoms of acute ankle sprain leading to lose of training and competition in athletes. The purpose of this randomized controlled trial was to investigate the effect of six weeks neuromuscular training with wobble board and rocker board on dynamic postural control and self-reported function in individuals with functional ankle instability. Twenty eight male athletes from physical education faculty voluntary participated in this study and randomly assigned to a training group (n=14) and a control group (n=14). The training program consisted of six weeks progressive supervised neuromuscular training with wobble board and rocker board. Self-reported function and dynamic postural control was measured using Foot and Ankle Ability Measure (FAAM) and FAAM Sport and modified star excursion balance test (MSEBT) respectively. The experimental group compared with control group had significant improvement in FAAM and FAAM Sport scores (P <0. 01) and in reach distances with the anterior، posteromedial and posterolateral directions of the MSEBT (P <0. 05). Six weeks progressive supervised neuromuscular training with wobble board and rocker board significantly improved self-reported and dynamic postural control as assessed with MSEBT in male athletes with functional ankle instability.

The main purpose of the present study was to investigate the kinematics and kinetics of successful versus unsuccessful basketball free throws using data from picture analyzer program and dynamic modeling. Six professional basketball players (age = 23±2. 09 years) participated in our study. The picture analyzer program was designed in MATLAB software to convert the two-dimensional coordinate obtained from two cameras picture (u & v) to the joints angles. The joint angles were given as input to the dynamic model. Outputs were obtained kinetic data including the angular impulse and maximum torque. Wilcoxon test using SPSS statistical software version 18 was used to compare successful and unsuccessful free throws at significant levels of 0. 05. The results showed that wrist joint (p ≤ 0. 046) had significantly more flexion in successful versus unsuccessful shots while elbow (p ≤ 0. 028) remained significantly less flexed in successful shots. Wrist and elbow angular velocity was found to be significantly higher in successful versus unsuccessful shots at the time of ball release. The results showed that there were no significant differences between successful and unsuccessful free throws in angular impulse but in successful free throws، wrist maximum torque was more than it in unsuccessful free throws (p ≤ 0. 046). In general seems increase the wrist angular velocity that it is due the greater torque، had been effected on successful free throws.

Balance involves a complex of dynamic interactions of vestibular، visual، and somatosensory information. The aim of the present study was to evaluate relationship between knee and trunk extensor muscles strength with balance. 297 male students of guidance level of Guilan Province were selected through cluster random sampling. Star excursion balance test and a dynamometer were used to measure balance and strength of knee and trunk extensor muscles respectively. Pearson correlation coefficient and multivariate regression were used to test the hypothesis of the study. α level was set 0. 05. The results of the study showed a significant correlation between three groups of muscles strength with balance. By regarding the results of the study، it seems that knee، hip and trunk extensor muscles strength have basic role in balance.

Take-off is considered as a critically important phase in Long Jumps. Efficient transformation of velocities from horizontal to vertical forms the fundamental goal of this part. The objective of this article is to compare the take-offs performed by elite Asian long jump athletes and their world-class counterparts. 37 performances from 8 male long jump athletes with averages of 7. 68±0. 28 m، in Fourth indoor Asian senior athletics championships held in Tehran were recorded at 300 Hz. The intended variables were analyzed using motion analysis software and one-sample t-test with significant level of 0. 05 was adopted to make comparison to data available on world class elite. Differences were observed both in velocity profiles and in take-off performances. Variables such as vertical (p<0. 001) and horizontal velocity (p<0. 001)، lowest knee angle at the take-off (p=0. 046) and the last stride length (p<0. 001) were lower and contact time (p=0. 003)، inclination angle (p<0. 001) and touch-down knee angle (p=0. 001) were found to be higher than the available data on world class elite athletes. Furthermore، a sharp fall of velocity in the first phase of take-off was observed. It would seem that those attending the Asian championships were unable to provide a suitable technical performance، although they were obviously familiar with the techniques. Constant supervision of practice sessions through implementation of motion analysis systems، to identify، reduce or eliminate technical mistakes is highly recommended. In addition، conditioning programs to enhance eccentric strength of knee extensors and thus improve the maximum velocities are highly recommended to improve individual records.

Children with disabilities due to physical limitations are at risk of lack of exercise and reduced physical activity. The purpose of this study was the examination of the physical fitness in children with sensory impairment. In this case-control study 16 blind children and 30 deaf children (6-12 yr) participated as the sample groups. 60 healthy children also participated as the control group. For assessing physical fitness the aerobic fitness (3minute step test)، muscular endurance (sit ups)، hand grip strength test، flexibility (sit-and-reach and trunk-lifting) and static and dynamic balance (modified flamingo test and Timed-up-and-Go) were measured. One-Way ANOVA and LSD post hoc test was used for data analyzing. Data analyze showed that hand grip strength test results of blinds were less than deaf and healthy subjects (p=0/007). Aerobic fitness in blind and deaf children were less than healthy children (p=0/001). There were no significant difference in the results of Sit and reach test among groups (p=0/365). However، there were significant difference among groups in Sit up (p=0/001) and trunk lift (p=0/001) test results. Static and dynamic balance test results showed significant difference between blind and deaf groups (p=0/001)، but there were no statistical difference between deaf (p=0/17) and healthy subjects (p=0/935). According to the findings of the present study، sensory impairment leads to poor physical fitness such as aerobic fitness، muscle strength and endurance and balance. Therefore، early screening of physical fitness and designing proper physical fitness and exercise training programs appears to be essential to improve children''s physical condition.