I remember explaining this before but what the hell. That article in ironman is complete bollox if that's what it says. Even if you are 80% ST you should still train for FT growth. No matter how many ST fibers you have they simply cannot do the things FT's can. They can't produce maximal force, synchronization, use ATP/CP energy system, increase explosiveness, maximize neural output, or another shitload of things. FT's have a much higher potential for size than do ST's and also have the greatest contractile:non-contractile ratio which makes them more "functional". You can also make yourself more FT by training for FT growth. No, you don't make new fibers you make your FT oxidative fibers more glycolytic. This means they can produce more force, amd basically become FT. And there are these contractile protein chains MHC IIX which are just inactive muscle fibers just waiting to be coverted to either FT or ST, and how you train is what determines what they become. Train for FT they become FT, train for ST they become ST. And blah blah blah.......