• Physical Therapy Korea
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• v.9 no.1
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• pp.1-15
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• 2002

The purpose of this study was to compare the balance and gait between fallers and non-fallers in elderly. A brief questionnaire was used to obtain the fall history. Twenty-seven women subjects were evaluated in this study. Eleven subjects and a mean age of 84.5 years (SD=4.6) were designated as the faller group. Sixteen subjects and a mean age of 80.3 years (SD=5.3) were designated as the non-faller group. The fall-related factors (mental status, balance, range of motion and muscle strength of lower extremity, sensation of foot, and cadence, walking velocity, stride length) were compared between faller group and non-faller group and measured. The results showed that faller group had significantly less range of motion of the hip flexion and knee extension, and strength of the knee extensor and ankle dorsiflexor and plantar flexor than non-faller group. The scores of the Functional reach test and One leg standing were significantly less in faller group than in non-faller group. Faller group showed less walking velocity and stride length compared to non-faller group. However, there was no significant difference in cadence during comfortable waking and fast walking between two groups. There were no significant differences in pressure, position sensory between two groups. These results suggest that exercise for improving the flexibility, muscle strength of the lower extremity and balance may be useful strategies to prevent fall in elderly. Further studies are needed to identify which specific factors are related to fall in the elderly population.

• Korean Journal of Applied Biomechanics
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• v.15 no.3
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• pp.161-173
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• 2005

Recently among several tennis techniques forehand stroke has been greatly changed in the aspect of spin, grip and stance. The most fundamental factor among the three factors is the stance which consists of open, square and closed stance. The purpose of this study was to investigate the relations between the segments of the body, the three dimensional anatomical angle according to open stance patterns during forehand stroke in tennis. For the movement analysis three dimensional cinematographical method(APAS) was used and for the calculation of the kinematic variables a self developed program was used with the LabVlEW 6.1 graphical programming(Johnson, 1999) program. By using Eular's equations the three dimensional anatomical Cardan angles of the joint and racket head angle were defined 1. In three dimensional maximum linear velocity of racket head the X axis showed $11.41{\pm}5.27m/s$ at impact, not the Y axis(horizontal direction) and the z axis(vertical direction) maximum linear velocity of racket head did not show at impact but after impact this will resulted influence upon hitting ball It could be suggest that Y axis velocity of racket head influence on ball direction and z axis velocity influence on ball spin after impact. the stance distance between right foot and left foot was mean $74.2{\pm}11.2m$. 2. The three dimensional anatomical angular displacement of shoulder joint showed most important role in forehand stroke. and is followed by wrist joints, in addition the movement of elbow joints showed least to the stroke. The three dimensional anatomical angular displacement of racket increased flexion/abduction angle until the impact. after impact, The angular displacement of racket changed motion direction as extension/adduction. 3. The three dimensional anatomical angular displacement of trunk in flexion-extension showed extension all around the forehand stroke. The angular displacement of trunk in adduction-abduction showed abduction at the backswing top and adduction around impact. while there is no significant internal-external rotation 4. The three dimensional anatomical angular displacement of hip joint and knee joint increased extension angle after minimum of knee joint angle in the forehand stroke, The three dimensional anatomical angular displacement of ankle joint showed plantar flexion, internal rotation and eversion in forehand stroke. it could be suggest that the plantar pressure of open stance during forehand stroke would be distributed more largely to the fore foot. and lateral side.