Just a curious kind of post. Is it possible for someone of my backround to go sub 4:15 in the mile, or am I underestimating the difficulty of this feat. Im a senior in hs and have ran consistently uninjured for the past 2 years. Last winter was hitting around 40 mpw, and during the track season around 35 mpw, ran 4:31, 2:02, and roughly 54 for the 400. Over the summer ran around 45-50 a week. This winter ive run 50-55 a week for around 3 months now, and have gotten my 1600 time down to 4:25. I reckon my 400 speed right now is roughly 53, and 800 around 2 flat. Haven't done super fast work yet so those might improve slightly come outdoor. The real question is with a few more years of training and building milage to much higher (ex. 70-80 mpw). Is it possible for me to run under 4 15. Or anyone of my nature. Or am I underestimating how big of a jump this really is?