How old were the actors in Over the Top (1987)?

Lincoln Hawk a hard-luck big-rig trucker takes us under the glaring Las Vegas lights for all the boisterous action of the World Armwrestling Championship. Relying on wits and willpower, Hawk tries to rebuild his life by capturing the first-place prize money, and the love of the son he abandoned years earlier into the keeping of his rich, ruthless father-in-law.