3 Genetically Skinny Guys Tell you how they Packed on Huge Amounts of Muscle Scientists have recently made some outstanding discoveries-like a black hole that’s 12 billion times bigger than our sun and a brand-new species of human ancestor that lived more than 2.5 million years ago. But skinny guys everywhere are still waiting for one important finding: the perfect (drug-free) formula for turning an ectomorph into a mesomorph, genes be damned. Sick of the wait, they’ve taken matters (and dumbbells) into their own hands. They’re essentially lab rats, testing various lifting techniques and hundreds of exercises, all in the hopes of changing their physiques. And a few have found methods that work for them. Sure, they don’t look like Schwarzenegger in his heyday, but they all packed on double-digit pounds of muscle and now buy bigger-sized clothing. So we reached out to three formerly-skinny guys to find out how they did it. Three years ago, Mike Shannon, a floor layer from Rossendale, United Kingdom, weighed 140 pounds. Now, at the age of 30, he’s 45 pounds heavier-almost all of it muscle. His secret: Throw out isolation exercises-which only work one muscle group-for big compound movements like the squat, deadlift, bench press, row, and pullup-which work multiple muscle groups at once. "I thought I was lifting before, but not really," he says. Shannon trains everything twice a week in 3-day blocks. During the first block, he lifts super heavy and does lower reps with long rest breaks between sets. Then he takes a rest day. During the second block, he lifts lighter and in the 6-to-15 rep range with shorter rests between sets. "The compound movements recruit a lot more muscle than single-joint lifts.