Some of my favorite Japanese people share a common trait: They hate the word ganbaru (頑張る). In fact, they resent being offered encouragement with phrases like ganbatte ne, ganbare, ganbatte kudasai or any of the other imperative iterations of the usually mindless exhortation directed at people experiencing adversity.
Those learning Japanese may be surprised that ganbaru could have anything other than positive associations, particularly since it is often directed at people trying to learn something! It is also commonly used by well-intentioned people to cheer sports teams, buck up depressed friends and galvanize employees of companies experiencing difficult challenges in business.
Though usually just written in hiragana, ganbaru can more properly be written using the character gan (頑), which is also used in terms such as stubbornness (ganko, 頑固) or ox-like stamina/strength (ganjō, 頑丈). Haru (張る) is a more nuanced term that carries the nuance of "erect" or "set up."