Background and Aim: Since many of people in their functional activities mostly place their knee joint in flexed position, the hamstring muscles tend to be shortened. On the other hand, shortness of these muscles affect the knee joint directly and the ankle and hip joints indirectly. It predisposes the individual to musculo-skeletal injuries. Thus, by early diagnosing and treatment of it, the tension may be decreased, the relaxation increased and the development of injuries can be prevented. In order to achieve this goal, various stretching techniques are used. The purpose of this study is to compare the effects of static and PNF stretching on shortness of hamstring muscles in 18-30 years young women.

  Materials and Methods: Thirty 18-30 years old nonathletic women without any history of pathology in hip, knee or back were selected. They were divided into three groups with 10 women in each group(static stretch, PNF stretch and control). The two stretch groups were received stretching program five days every week for three weeks, while the control group was not.

  Results: The range of knee extension of both groups of static and PNF stretching increased (p<0/05). However there was no significant difference between these two groups (p>0/05).

  Conclusion: Employing of both methods (static and PNF stretching) increase the hamstring muscles flexibility. However there was no significant difference between two groups in increasing rang of knee extension.

  Key words: Hamstring muscles, static stretching, PNF stretching

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