Nobody told the poor guy to run out and buy florescent knee high socks, shmedium t-shirts, or to act like a d-bag. Or to do Olympic lifts till failure so he can for sure exhibit very poor form by the end and probably blow his L5.
Now to the real topic of the thread.
I would suggest adding weight lifting in to your workout, especially legs. You want to build endurance (i.e. 4x10 at probably 65-75% of your maximum). And also like most everyone is stating, high intensity anaerobic workouts (sprints, hills, build ups, fartleks, ect) are going to increase your VO2max. Increasing the duration and lowering the intensity will increase your muscle endurance.
Good luck.