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Background and Aim: Several biomechanical and clinical studies have examined the apparent myoelectric silence of the lumbar spine extensor musculature during lumbar flexion from a neutral upright standing posture.

Objective: The purpose of this study was to investigate the relationship between trunk flexibilitiy and flexion relaxation response of the the lumbar erector spinae

Material and Methods: 30 female healthy students were participated in this study which They were arranged in three groups on toe touch test (low flexible,  normal and high flexible).The surface electromyographic from the lumbar erector spinae muscles as well as flexion angle of the trunk, hip and lumbar were recorded. The angle in which electromyographic diminished during flexion and initiated during extension was determined and subjected to one way Anova to determine any significant differences  in the flexion-relaxation response between three groups.

Results: The erector spinae muscles were relaxed in  larger angles during flexion and initiated activity significantly earlier during extension in high flexible group (p<0/001). pearson correlation indicate that there were high correlation between trunk and hip angle during full flexion (r=0/88 p<0/001) and no correlation between trunk and lumbar angle (r=0/1 p< 0.3).

Conclusion: The results indicated that individuals with more flexible trunk , the erector spinae muscles gets relaxed in further angles of the trunk and the hip, furthermore while returing to the upright posture ,this muscle is recruiting sooner than two other groups .the biomechanical basis of this finding relies in ligamentous and passive tissues properties of individuals with different Flexibilities of the trunk which can effect there recruitment pattern of active tissues.

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Background and aim: Muscle flexibility is an important component of physical fitness and injury prevention.

Passive Stretch can be effective in lengthening and making hamstring more flexible. Popliteal angle measurement is one of the most simple method in studying the efficiency of these methods however, in goniometry measurement, there is not any data about muscle tension and any proper judgment about flexibility.  The goal of this study is to evaluate length and stiffness of the hamstrings by Quick Release Movement before and after the passive stretch.

Materials and methods:14 men (20-30 years old) with shorted hamstring (20 degree or more ext lack in passive knee ext test by popliteal angle measurement) participated in this study. Before and after exercises, popliteal angle  and muscle stiffness  were evaluated with digital goniometer and  Quick Release Movement technique respectively. Evaluation of stiffness was performed in flexion and extension positions.

Results: A significant increase in hamstring length was observed. (P<0.05) There was decrease in stiffness in both position of flex and ext but it was significant when in extension state.(P<0.05)

Conclusion: Findings of this study demonstrate passive stretch's effectiveness in increase muscle length and lessening muscle stiffness. In addition Quick Release Movement can be a suitable method for measuring muscle stiffness.

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Background and Aim: One of the risk factors in sports injuries is inappropriate flexibility of muscles, which leads to pain, decrease range of motion and functional limitation in sport or daily activities and affects the athletes’ quality of life. The aim of this study was to investigate the relationship between flexibility of calf muscles and functional status of athletes with ankle injuries.
Materials and Methods: Thirty male athletes with ankle injuries (mean age ± SD, 22.63 ± 3.94 range: 18-40 years) participated in this study. Ankle dorsiflexion of affected and non-affected sides were measured with a goniometer. FAOS (Foot and Ankle Outcome Score) questionnaire was used to evaluate the functional status of ankle.
Results: The relationship between flexibility of calf muscles in the affected extremity, and total score of the functional questionnaire, was not statistically significant (P>0.05). While the relationship between the flexibility of muscles and functional questionnaire's total score in the non injured extremity was significant (P = 0.004, r = 0.51).
Conclusion: This study revealed that although the athletes who have more flexibility of calf muscles, show better functional status of ankle but there is not necessarily a relationship between inflexibility of the muscles and lowered functional status.

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Background and Aim: Acquaintance about different stretching methods and applying of the most effective them is necessary to improve sport skills, prevent sport injuries and accurate treatment. Several techniques of stretching exercises are recommended to improve flexibility and among them static, dynamic and PNF techniques have been widely used. The purpose of present study was to compare immediate 24 and 48 hours effects of static, dynamic and PNF stretching techniques on boy students hamstring flexibility.

 

 

 

 

 

Materials and Methods: The study was Quasi Experimental with one pre-test and 3 post test. One hundred and sixty eight high school students (age, 15.7 ± 0.07 years height, 171.2 ± 0.56 cm weight 63.9 ±1.14 kg) participated in this study. Participants randomly assigned into for groups.  Group one performed static, group two dynamic, group three PNF techniques of stretching and fourth group considered as a control group. The groups participated during 3 days on this study. To measure hamstring flexibility sit and reach test was administered pre and post intervention.

 

 

 

 

 

Results: ANOVA with repeated measures were used to analyze the data. The finding revealed significant differences between pre and post tests for all three stretching techniques immediately after stretching exercises while no changes was reported for control group (P&le0.05). Tokays fallow up tests indicated that 24 and 48 hours post intervention effects of static and PNF stretching were remained while dynamic stretching effect was disappeared 24 hours post intervention.

 

 

 

 

 

Conclusion:  Based on the finding of this study all three stretching techniques improved immediately hamstring flexibility while the effect of static and PNF techniques of stretching remained up to 48 hours post stretching. As a result, static and PNF stretching are more efficient than dynamic stretching.

 

 

 

 

 

Keywords: PNF stretching, Static stretching, Dynamic stretching, Flexibility    

 

 

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Background and Aim:: Muscular shortness is one of the most common musculoskeletal impairments. It may occur as a result of trauma or even a sedentary life style and cause clinical symptoms. Hamstring muscle, due to its functional roles, is prone to injuries during physical activities. Research has shown that decreased hamstring muscle flexibility may lead to lower extremity injury. The goal of this study is to compare the effects of myofascial release (MFR) and muscle energy technique (MET) effects on hamstring muscle flexibility. 

Materials and Methods: Twenty four non-athlete healthy subjects (means ± SD= 26/12 ± 5.4 Years) were randomly assigned to two groups; myofascial release group and muscle energy technique group. Passive range of motion (ROM) of knee extension was measured using a digital goniometer before and immediately after the intervention.

Results: There was a significant increase in the knee passive range of motion immediately after both interventions (in MFR group p=0.000 and in MET Group p=0.000).The amount of knee extension increase was greater in myofascial release group (p=0.023).

Conclusion: Both MFR and MET can increase hamstring muscle flexibility; however, in this study MFR has shown to be more effective than MET.

Keywords: Flexibility, Muscle energy technique,  Myofascial release technique,  Hamstring muscle