This procedure is known as bullfighting because, under conditions in which there is no drop-off, the "fliers" must rely completely on running to keep the glider overhead.
而這個程序之所以被稱為鬥牛，就是因為在沒有高度落差的情況下，飛行者必須完全靠奔跑緊緊跟住傘的速度。