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Introduction: Falling phenomenon is one of the prevalent and serious problems among the elderly that brings about disability and reduction in quality of life for them. Investigating the causes of the fall and identifying the elderly who are at risk of falling, with the aim of reducing and preventing collapse, are deemed integral issues. Hence, this study investigates the role of muscle strength and range of motion of the lower extremity affective in the elderly's fall.
Method: In this study, a systemic search was conducted through the electronic databases, including PubMed, Google Scholar, MAGIRAN, IRANDOC, and SID. Necessary searches through the articles published from 1984 to August 2017 for English and Persian keywords were carried out. The English keywords sought included elderly, older adult, geriatric, aging, lower extremity range of motion, fall, gait, and lower extremity muscle strength; the Persian ones included the elderly, lower extremity range of motion, lower limb muscle strength, balance, walking, and slipping. After the initial screening performed based on the inclusion and exclusion criteria of the study, the articles published in English and Persian, in terms of the current subject, were investigated.
Results: Forty-three articles were selected, and they examined the role of lower extremity muscles and joints in the case of fall by the elderly using the following methods:  1. Age-related weakening of muscle strength and lower extremity range of motion; 2. The correlation between muscle strength as well as range of motion and balance and walking abilities in the elderly; 3. Comparison of muscle strength and range of motion in the elderly (with a background of falling or lack of such a background) and those in the youth; 4. The effect of certain muscles and joints of the lower extremities on the elderly’s balance, fall, and walking.
Conclusion: Based on the above findings and results, it appears that as aging grows interaction of muscle strength and lower extremity range of motion with power balance increases. Therefore, the results of this study indicate that measuring muscle strength and lower extremity range of motion is of great value in terms of the assessment of balance disorders and functional skills in the elderly.



 

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Introduction: In recent years, the effect of cognitive exercises on improving gait parameters has been studied, but the effects of these exercises on coordination inter-joint of the lower limbs have received less attention. Therefore, the aim of this study was to investigate the effect of dual task motor-cognitive training on inter-join coordination during walking in elderly with balance impairment.
Methods: 30 elderlies with the mean age of 73.8 participated in this study. The elderly's functional balance score (Berg) was lower than 52, and the Mini Mental Status Exam (MMSE) was higher than 23. These individuals were purposefully divided into two groups, the experimental group participated in 24 training sessions after the pre-test and the control group engaged in normal daily activities. To assess the inter-join coordination, the participants had to walk a 12-meter path and the coordination was recorded at the sagittal level in four gait cycle by vector coding. The data were analyzed by repeated measures and one-way ANOVA at the significance level of p < 0.05.
Results: The findings of this study showed that after training, the amount of coupling angle has decreased in most gait cycles. The greatest effect of dual training in the experimental group is in the loading response and push off (p <0.05). Some temporal characteristics of gait, such as walking speed, were also significantly improved by dual task training (p <0.05).
Conclusion: According to the results, it can be concluded that the dual task training had improved the coordination characteristics between the lower limbs joints. This change in coordination with the improvement of some temporal parameters was a sign of increased balance and better posture control in the elderly with balance impairment.