A victim of bullying is cajoled into taking boxing lessons, usually from a cartoonishly macho alpha-male character. The victim usually ends up finding an alternate, non-violent but always interesting means of dealing with the bully. Oddly, Eastern martial arts (karate or kung fu) are generally considered to be an acceptable way of dealing with bullying. Krav-maga, not so much.
Examples [tvtropes.org]