نشریه مطالعات طب ورزشی
پیاپی 16 (پاییز و زمستان 1393)

The knee positions could be parameters for injury of handball players in landing. Preventive exercise programs may decrease the injury of players. The aim of this study was to investigate the effect of a Neuromuscular Exercise Program on lower limb kinematics and single leg stability in male handball players. 40 handball players (Regular Training: n=20، height 187. 7±5. 5 cm; weight 89. 0±10. 1 kg; age 25. 4±13. 6 years; handball experience 11. 6±6. 4 years and neuromuscular training: n=20، height 185. 3 ±6. 4 cm; weight 86. 8±13. 6 kg; age 24. 2±3. 8 years; handball experience 10. 8±3. 3 years) were selected from two clubs participating in Iran Super League on 2012-2013. There were significant differences between the two groups in inward rotation of femur، knee valgus angles and single leg stability. No significant difference was found in knee flexion angle. Neuromuscular training can improve overall performance and reduce lower extremity valgus angle and internal rotation of the knee during landing with one leg. It may help handball players to prevent knee ligaments injuries، especially ACL، during competition season.

The aim of this study was to evaluate the differences in frequency content of the ground reaction force during running with regular shoes (Polyvinyl chloride); the shoes containing Nano shoes in their outsole (Nano shoes) and barefoot. Fifteen physical education active male students (age 24±3 years، height 176±5 cm، and weight 69±8 kg) without injury randomly ran on the force plate placed in a 15 meters runway in Nano shoes، Polyvinyl chloride and barefoot conditions. Fourier transformation of ground reaction force was determined to calculate 99. 5% power frequency، median and bandwidth frequencies. One-way ANOVA test was applied to show differences. Significant reductions were seen in 99. 5% frequency and median frequency of anterior-posterior and vertical ground reaction force during running with Nano shoes and Polyvinyl chloride shoe sole as compared to barefoot condition. Also، no significant differences were observed in median and bandwidth frequencies. Nano shoes compared to barefoot running could lead to more frontal stability. However، using Nano shoes compared to PVC didn’t show any significant change in frequency contents.

Endurance of trunk and pelvic girdle muscles are important for good posture. The Matthiass'' arm-rising test is used to assess posture and postural related muscle performance. The objective of this study was to investigate the relationship between score of Matthiass arm raising test with endurance of trunk muscles. For this purpose، 118 boys with the mean age of 10. 21±0. 86 years، weight of 36. 38±10. 18 kg and height of 140. 11±7. 54 cm were selected. Matthiass Test was recorded using digital camera and their compensatory movements were analyzed by computer. Subjects were classified in three groups according to compensatory movements; normal، weak and poor. The endurance of trunk flexor muscles was measured by modified Sorenson test. Back extensor muscles were measured by McGill endurance test. A lateral trunk flexor muscle was measured by McGill side bridge endurance test. The results indicated a significant relationship between the score of Matthiass Test and endurance of trunk muscles. According to the outcome of the current study، it can’t be concluded that Matthiass test has significant relationship with endurance of trunk muscles. However، it is suggested for screening of schoolchildren in large-scale studies. However، further studies with substation subjects are needed to help definite conclusion.

Finding the optimal techniques is one of the aims of sport biomechanics science. According to previous soccer kick studies، the pattern of optimal technique has been computing by analyzing the kinematic and kinetic parameters of elite soccer player. The purpose of this study was finding the optimal soccer kick pattern in forward swing phase to achieve a maximum speed shot. The solution approach which is suggested to produce the optimal technique is to use the mechanical modeling by applying the motion equations. This model has some advantages compared to experimental study such as changing the model parameters separately، low cost and run repeatedly the model. A two-dimensional four-link dynamic model is introduced and by applying the appropriate constraints، the genetic algorithm is used to achieve the optimal technique. The computed pattern was compared with six skill subject’s patterns that Acquired by cameras (240Hz). The results showed significant deference in joints angular displacement patterns between computed and subjects techniques. Also، the computed pattern velocity increased 62. 5 percent more than subject’s pattern and the computed pattern was similar to reported in previous studies. Therefore، the computed pattern is valid for human according to human body physiology and mechanics. Using the model in this study can create interaction between joint and segments and enhance Motion-Dependent Moment in distal segment and improve speed and quality of the kick. Therefore، it is important and necessary to enhance muscle strength and improve neuromuscular coordination. In a nutshell، this model is an apparatus which can available for trainers to teach optimal technique of soccer instep kick to athletes specifically.

The aim of this study was to compare the effects of traditional exercises and body weight supported training (BWSTT) exercises on functional ambulation profile in paraplegic spinal cord injured people. 17 individuals with paraplegic spinal cord injury (ASIA B،C classification) having average of SCI history 14 months، age 32. 53 ± 1. 793 years، height 175. 71 ± 1. 658 cm، weight 71. 59 ± 2. 442 kg، and body mass index (BMI) 23. 18 ± 0. 828 kg/m2 were selected. The subjects were randomly assigned to BWSTT group (N=10) and Traditional exercises group (N=7). The subjects trained for 12 weeks، four times per week and 60 min per session. BWSTT included 15 min warm-up on fixed gear bike، 45 min BWSTT with 50% body weight and 10 min cold-down finally. 10% load was added each week. Traditional exercises included 15 min warm-up plus 45 min stretch and resistance exercises، walking with parallel and 10 min cold-down finally. data showed that there were significant differences in serum Alkanline phosphatase، Osteocalcine، Bone mineral content (BMC) of the femoral neck، Bone mineral density (BMD) at femoral neck، Bone mineral content (BMC) at the lumbar spine، Bone mineral density (BMD) at the lumbar spine between BWSTT and traditional groups. BWSTT training may reduce bone loss in paraplegic persons and may be prescribed as an effective intervention for treatment of osteoporosis.

The aim of this study was to compare the effects of traditional exercises and body weight supported training (BWSTT) exercises on functional ambulation profile in paraplegic spinal cord injured people. 17 individuals with paraplegic spinal cord injury (ASIA B،C classification) having average of SCI history 14 months، age 32. 53 ± 1. 793 years، height 175. 71 ± 1. 658 cm، weight 71. 59 ± 2. 442 kg، and body mass index (BMI) 23. 18 ± 0. 828 kg/m2 were selected. The subjects were randomly assigned to BWSTT group (N=10) and Traditional exercises group (N=7). The subjects trained for 12 weeks، four times per week and 60 min per session. BWSTT included 15 min warm-up on fixed gear bike، 45 min BWSTT with 50% body weight and 10 min cold-down finally. 10% load was added each week. Traditional exercises included 15 min warm-up plus 45 min stretch and resistance exercises، walking with parallel and 10 min cold-down finally. data showed that there were significant differences in serum Alkanline phosphatase، Osteocalcine، Bone mineral content (BMC) of the femoral neck، Bone mineral density (BMD) at femoral neck، Bone mineral content (BMC) at the lumbar spine، Bone mineral density (BMD) at the lumbar spine between BWSTT and traditional groups. BWSTT training may reduce bone loss in paraplegic persons and may be prescribed as an effective intervention for treatment of osteoporosis.