The foot radical ⻊ does the work while 兆 lends the sound. 兆 was the pattern of cracks on oracle bones — read as omens — and something startled by an omen does exactly what 跳 describes: it leaps.
心跳 'heartbeat' is the jump inside your chest; 跳槽 'jump the trough' is how Chinese describes switching jobs — an ox leaving its feeding spot for a better one. Job-hopping season after Spring Festival is literally called 跳槽季.
A foot ⻊ startled by an omen 兆 — it JUMPS.
广场舞 square dancing draws millions of dancing aunties every evening — 跳广场舞 is arguably China's biggest participatory sport.