Headflip

He executed a series of gulps and headflips, veritably flinging the meat down his throat.

Source: wiktionary

Rubicon, fourteen, would often amuseus with his parlor tricks, with his handstands and footswings and headflips, but he was the only skilled among them.

Source: wiktionary

Already, those sperm snapped around like springs, also lashed their tails, did headflips and cartwheels, crowded one another, swam in circles, and generally postured like pent-up adolescents eager to be off.

Source: wiktionary

She shrugged, popped her gum, straightened up with a little headflip.

Source: wiktionary