1. Gregg Valentino

He started lifting weights at age 13 and is regarded by many as the biggest body builder ever. After over 23 years of training naturally Gregg decided to experiment with steroids. During this time his arms grew from an impressive 100% natural 21″ to an in-human 28

2. Markus Ruhl

Well known for his freakish size, german Markus Rühl is a former IFBB professional bodybuilder. He possesses some of the biggest shoulders in bodybuilding history, and is one of the strongest bodybuilders alive along with Johnnie O. Jackson and Ronnie Coleman.

3. Ronnie Coleman

Born May 13, 1964 in Bastrop, Louisiana, Coleman is a retired American professional bodybuilder who shares the record of eight straight wins as Mr. Olympia. He also holds the record for most wins as an IFBB professional with 26 wins.

More details and pics - http://nairabrains.com/2014/09/worlds-biggest-bodybuilders-the-muscles-these-guys-pack-is-tremendous/