Effect of the Shape and Height of Walker Handles on Muscle Activity in Upper and Lower Extremities During Sit-to-stand

Abstract

Objective: The research compares the muscle activity of upper and lower according to the shape and height of handle in sit to stand(STS). Method: The research 20 healthy adults in their twenties who were randomly assigned a different type and height of walker handle. The muscle activity of upper trapezius, biceps, triceps brachii, flexor carpi ulnaris, extensor carpi radialis, rectus femoris, biceps, anterior tibialis and calf STS were measured using wireless electromyogram. The value of the measured electromyogram signal was obtained and the muscle activity was subsequently normalized into the value into maximum voluntary contraction of normality was performed for general features of the subject and repeated two-way ANOVA(analysis of variance) was used for the analysis. Results: The upper trapezius, triceps brachii, flexor carpi ulnaris, rectus femoris, biceps and tibialis anterior showed significant in muscle activity according to the height of the walker, while the extensor carpi radialis and flexor carpi ulnaris showed significant in muscle activity according to the shape of handle. Conclusion: Using walker with lower handle height compared to regular walkers will contribute to preventing unnecessary muscle contraction of upper and enabling effective movement with lower. Moreover, the shape of handle that supports forearm in pronation can be helpful in preventing muscular skeletal damage of wrist that can occur from repeated use of walker.