Developmentally delayed children with different muscle tone have different muscle activity and acceleration during sit-to-stand.

Developmental delays cover a wide range, with different movement characteristics occurring depending on differences in muscle tone. We aimed to investigate muscle activity and acceleration during sit-to-stand in developmentally delayed (DD) children with different muscle tones. Forty participants were divided into three groups: typically developing (TD) children (n=18), DD children with hypertonia (n=12), and DD children with hypotonia (n=10). Electromyography was used to measure muscle activity and BTS G-Walk was used to measure acceleration. As a result, the activities of the rectus abdominal muscle and quadriceps muscle were lower in DD children with hypertonia than in TD children (<0.05). The activity of the tibialis anterior muscle was higher in DD children with hypotonia than in TD children (<0.05). The trunk angle was greater in DD children with hypotonia than in TD children (<0.05), and vertical acceleration was lower in DD children with hypertonia than in TD children (<0.05). Based on these differences, we will be able to provide intervention programs appropriate for the characteristics of DD children with different muscle tone.