Star power distinguishes lighthearted Korean arm wrestling drama ‘Champion’

There’s little in the underdog sports dramedy “Champion” that feels vital, aside from its star. Korean American actor and athlete Ma Dong-seok (billed here as “Don Lee”) has a grace that makes him fun to follow, even in an over-slick retread of Sylvester Stallone’s “Rocky” and “Over the Top.”

Ma…