Background: Although rectus femoris (RF) eccentric training and static stretching (SS) have been reported effectively on lumbar flexibility, and muscle architecture, most studies are results using machines and long-term effects. Therefore, we want to investigate the effect of Reverse Nordic Hamstring Exercise (RNHE), a self-eccentric training, by immediately comparing it with SS. Objectives: To compare the RNHE and SS of RF to show the effects of lumbar flexibility, and fascicle length (FL). Design: Randomized controlled trial. Methods: A total of 30 study subjects were randomly allocated into an experimental group(Reverse Nordic Hamstring Exercise) and a control group(Static Stretching). Before and after the intervention, the subject performed fingertip to floor test (FFT) to evaluate the flexibility of the lumbar spine and measured FL through the SONON 300L (Healcerion Inc., Seoul, South Korea). Results: There was a significant effect on lumbar flexibility within both groups (P<.05), also there were clear results between the two groups (P<.05). FL showed a significant increase in RNHE (P<.05), but not in SS, and there was a no significant difference between the two groups. Conclusion: RNHE is effective in improving lumbar flexibility, and FL of RF muscle.

The purpose of this study is to provide fundamental clinical data for the treatment plan and rehabilitation of patients with cervical hypolordosis by comparing the cervical headache and muscle activity after cervical stretching exercise and cervical traction, which are generally applied to patients with cervical hypolordosis. The research subjects included 20 patients without gender division who were diagnosed with cervical hypolordosis. After applying cervical stretching exercise and cervical traction for six weeks, cervical headache and the activity of the muscles around the cervical vertebra(upper trapezius muscle, sternocleidomastoid muscle, splenius capitis muscle, and anterior temporal muscle) were investigated and the following results were obtained. In a comparison of the within group intervention effects of the two groups, cervical pain statistically significantly decreased in the cervical stretching exercise group. According to the results of analyzing the change of muscle tension in the upper trapezius muscle, both the cervical traction group and showed a statistically significant within group difference in the left and right side. According to the results of analyzing the change in the muscle tension of the splenius capitis muscle, both groups showed a statistically significant within group difference in the left and right side. In a betweengroup comparison, a statistically significant difference in the right side was observed. These results confirm that cervical vertebra traction and cervical stretching exercise decrease the cervical headache and muscle activity of the upper trapezius muscle and the splenius capitis muscle among patients with cervical hypolordosis.