The modern pentathlon is a very complex sport. Swimming, fencing, show jumping, running and shooting have to be completed by the athlete in one single day. Since 2009 running and pistol shooting are staged in one event, which is called the combined event. This change has led to new demands for the athletes; the understanding of this new event can help reveal new training methods. Therefore performance factors, of the new combined event have been identified with the aid of literature. One of these factors is shooting performance. Shooting performance takes not only a crucial part in the outcome of the combined event, but also in the outcome of the whole modern pentathlon. A good shooting performance on the other hand, depends on many other factors. One of these factors is the so-called postural balance; the ability to control the upright stand in a balanced way. The purpose of this work, was to determine how and if the running and different stances affects postural balance and as a result shooting performance. During two series of test, five modern pentathlon athletes completed at each series one simulated combined event. Variables such as heart rate, postural balance and shooting performance were measured in order to answer the constructed questions. The results showed different findings. The comparison of the two different stances revealed an advantage respective shooting performance for the normal stance, even though there were no significant differences in postural stability between the two stances. Physical strain induced by running showed no significant effect on postural stability. Moreover no correlation was found between postural stability and shooting performance. Postural stability doesn?t affect shooting performance as much as it was believed. It seems that there are other factors which play a more important role for shooting performance in the combined even. Heart rate and vertical forces showed significant differences for the three shooting series.