Originally Posted by Josh Heinrichs
There's no point trying to simultaneously pursue two goals at the complete opposite ends of the spectrum, which is what you are doing by combining long distance running with heavy squats. You will end up good at neither. Decide whether you want to do well at long distance running, and if so, train appropriately for that. If you want to get strong and powerful, forget the distance running and squat heavy for 3 x 5 (or 5 x 5 etc.).
This is about as accurate as it gets. Haile Gebrselassie can't squat heavy/Hossein Rezazadeh would likely struggle in a marathon.