To study with great effort and determination; literally to tie one's hair to a beam and prick one's thigh with a needle to stay awake.

To study with extreme diligence and perseverance; from the stories of Su Qin who pricked his thigh with a needle and Sun Jing who tied his hair to a ceiling beam to keep from falling asleep while studying.

to study assiduously and tirelessly; literally "to hang one's head from a beam and prick one's thigh with an awl" to stay awake and focused