Strength training seems to be an important element for the improvement of performance in middle and long distance running events. In particular, strength contributes more in the running events with high running velocity (improves running technique and running economy). Maximal strength, power endurance and strength endurance are the kinds of strength that donate in middle and long distance running performance. The improvement of maximal strength achieved through muscle hypertrophy is the base of the special strength. Special strength enhances through the improvement of explosive strength, depending of the meta-bolic demands of every event. Training dose response is made according to the percentage of VO2max, the number of repetitions, the exercise duration and the brake-time between each set, which is depending on the intensity and duration of the exercise. Strength endurance seems to be more important in middle distance than in long distance running events. The methods that are used for the improvement of strength endurance are the continuous method and moderate interval training. Additionally, the improvement of strength endurance is depending on the energy demands are chosen every time: exercise intensity up to anaerobic threshold (marathon, aerobic strength endurance), exercise intensity from anaerobic threshold to maximal oxygen uptake (10000m, 5000m, moderate strength endurance), exercise intensity higher than maximal oxygen uptake (800m, 1500m, anaerobic lactic endurance).