Effects of visibility and types of the ground surface on the muscle activities of the vastus medialis oblique and vastus lateralis.

[Purpose] The purpose of this study was to compare the effects of visibility and types of ground surface (stable and unstable) during the performance of squats on the muscle activities of the vastus medialis oblique (VMO) and vastus lateralis (VL). [Subjects and Methods] The subjects were 25 healthy adults in their 20s. They performed squats under four conditions: stable ground surface (SGS) with vision-allowed; unstable ground surface (UGS) with vision-allowed; SGS with vision-blocked; and UGS with vision-blocked. The different conditions were performed on different days. Surface electromyogram (EMG) values were recorded. [Results] The most significant difference in the activity of the VMO and VL was observed when the subjects performed squats on the UGS, with their vision blocked. [Conclusion] For the selective activation of the VMO, performing squats on an UGS was effective, and it was more effective when subjects' vision was blocked.

Study on the Usefulness of Sit to Stand Training in Self-directed Treatment of Stroke Patients.

[Purpose] This study sought to determine the usefulness of sit to stand training in self-directed treatment of stroke patients. It examined the effect that sit to stand training has on balance and functional movement depending on the form of support surfaces. [Subjects and Methods] Thirty stroke patients were randomly sampled and divided into an unstable support surface group (15) and stable support surface group (15). In order to identify the effect depending on the form of support surfaces, 15 minutes of support surface training plus + 15 minutes of free gait training was performed. [Results] The results of the unstable support surface training showed that the corresponding sample t-test results were significant for the 7-item 3-point Berg balance scale, timed Up and Go test, and 6-minute walking test. The independent samples t-test, showed that there were significant outcomes in step length on the affected side, and step length on the unaffected side. [Conclusion] In conclusion, the sit to stand training on stable support surfaces was not as effective as the training using unstable support surfaces, but it is a simple and stable exercise with less risk of falls during training. It can also be performed alone by the patient in order to increase endurance and dynamic balance ability. Therefore, it is considered a useful exercise that can be performed alone by the patient outside the treatment room.