It is necessary to analyze whether your goal is to be bottom runners or sprinters. If what you are long distances, or if, on the other hand, you better move at short distances.
If your case is approaching the first of the options, then you have an obligation to try to roll and predisposed to get many minutes. At the end of a month should sentimentalizing you make the same distances in less time.
It is a type of very homogeneous training in this aspect, with little room for variety. Big muscles, are not required so you can not do much gym work.
On the contrary, there is an obligation to carry very well diet, since any added pound you weigh, as if they were three.
In the second case, there are some more options. Those who try to improve the 100, 200 or 400 meters, have the possibility of train series of these same distances or even superiors.
An muscular and strong legs allow a greater stride and, therefore, meters that will make you save time and distance. Therefore, you will find more body volume corridors.In addition, if what yours are, ultra short distances as the 60 or the 100 meter dash, you must then prepare a fitness program, especially oriented to the legs.
In this case, you can start with a series of Farleys or changes of pace, which also achieved an increase in resistance to the higher intensity exercise. And even the usual rise of running stairs shall have the same effect.
In both cases, the diet is important. Not think that food is burned running, because what we try to achieve is, precisely to be lighter.
In the case of the sprinters, weight is greater, but helps to achieve our goal, since it is a very clean. Free of fats that may delay our progress.