Giancarlo Stanton trains heavy and hard. He has been quoted as saying he hates road trips because "there are never heavy enough dumbbells for me. there is never anything heavier than light 100#s"
As for "exit velocity," keep in mind that they've only been measuring this for 3 years. It's a shame they didn't have it for Bonds or for Ted Williams. Here's the estimated trajectory for the famous "red seat" HR at Fenway:
ESPN Home Run Tracker :: Hit Tracker Highlight Home Runs
And on the topic of baseball (snore), Jeff Passan's new book The Arm has some interesting history on Tommy John Surgery (torn UCL), in the context of increased shoulder size/strength without commensurate lower body strength. One of the better baseball books since Moneyball IMHO