His heavy build meant that he regularly portrayed a thug in his films, particularly earlier in his career in westerns.

Brega stood at 6 feet 4 inches (1.93 m) and well over 250 pounds (110 kg) at his heaviest but after the 1960s slimmed down significantly.

He was a butcher before he drifted into acting, where his heavy physique ensured him a plethora of character roles.

Debuting with director Dino Risi, he then played some minor roles in Sergio Leone's Spaghetti Western movies: A Fistful of Dollars, as Chico; For a Few Dollars More, as Niño;[1] The Good, the Bad and the Ugly as Corporal Wallace; and also as a gangster in Once Upon a Time in America.

Later in his career he had comical roles with director Carlo Verdone, such as in Un sacco bello and Talcum Powder.