Mass moves mass. We've all heard it. In a strength setting? Largely true. But that same mass you're building to move weight? You've got to carry it over distance. Every stride. Higher impact load. Higher oxygen cost. More fatigue. The interference effect isn't just conflicting training signals - it's literally the weight you're moving through space. Me and Dr Phil went deep. Hunter-gatherer principles, cross-training and why heavier athletes need to slow down progression. Find out more ab...