Tae kwon do

"Tae kwon do" was an earth martial art often taught to schoolchildren and used in both athletic competition and self-defence.

Clara Oswald claimed to have taken tae kwon do lessons, though she didn't have much opportunity to demonstrate said abilities. (TV: Robot of Sherwood) She later took her Year Seven students for tae kwon do lessons, rendering her unavailable to join the Doctor on an adventure. (TV: The Woman Who Lived)