In the only training book of its kind, Paul Kelso expands the "shrug principle" with dozens of variations that improve muscularity and the competitive lifts. "Trap bar" and rib cage enlargement programs are included.
Kelso's articles in Powerlifting USA, Iron Man, Muscular Development, and Hardgainer, plus books The Kelso Shrug System and Powerlifting Basics: Texas-Style, have spread these ideas worldwide.