A client asked Louis how Instagram influencers stay shredded all year. The short answer: it's their job, many are on PEDs they won't admit to, and the sacrifices don't show up on camera.

Louis and Brad cover both ends of the body fat scale. They lay out the ranges for men and women, from stage-lean to obese, and explain what happens at each extreme. Too lean costs you hormones, libido, recovery, joint comfort, mood, and your social life. Too much body fat, especially visceral fat around the organs, raises the risk of type 2 diabetes, heart disease, fatty liver, and sleep apnea. They also cover the real upsides of being lean, including better insulin sensitivity and power-to-weight ratio.