Base Training
Global Cycling Network has many videos regarding our sport. This one about base training was recently posted is one in my mind that is so very important. This is why when we first hit the road in the spring we keep the speed a little slower and the mileage less until your form starts to improve.
I would like you to consider commuting to work on the bike if you don't already. Even if it's just a couple times a week 2x per day rides will change your fitness dramatically. Something to consider this coming spring.