elongate

1. V-T/V-I If you elongate something or if it elongates, you stretch it so that it becomes longer. (使)拉長(zhǎng); (使)延長(zhǎng)[正式]

"Mom," she intoned, elongating the word. “媽媽，”她拖長(zhǎng)了聲音，緩緩地說道。

In this exercise, the muscles are elongating rather than contracting. 在這項(xiàng)運(yùn)動(dòng)中，肌肉是在延伸而不是在收縮。