Meaning of the word "exert oneself" in English

What does "exert oneself" mean in English? Explore the meaning, pronunciation, and specific usage of this word with Lingoland.

exert oneself

US /ɪɡˈzɜːrt wʌnˈsɛlf/
UK /ɪɡˈzɜːt wʌnˈsɛlf/

Idiom

to make a great effort; to try very hard

Example:
You'll have to exert yourself more if you want to finish on time.
He rarely exerts himself at work, preferring to let others do the heavy lifting.