Breathing, leg, arm action and movement coordination skills take place during swimming lessons. It is used in a variety of exercises in the water. Water is a special environment in which people are suffering from irrational movements. Swimming crawl in the back and the chest irrational actions leg caused by a failure in the thigh extension. At the hips extension are involved 5 muscle groups - agonists, synergists, converter, fixtures and antagonists. Of these are the postural and phasic muscles. The postural and phasic muscles must be in balance condition to make rational movement. For various reasons, many people in this muscle imbalance is reinforced and the irrational expressed as irrational movements, walking as well as swimming crawl on chest and back. Purpose: To determine the effect of swimming teaching process on the functional condition of the muscle group. Terms of Reference: To determine m.gluteus m.iliopsoas functional condition of students with low levels of swimming skill in the beginning of swimming teaching. Develop swimming skills, promoting rational swimming technic. To determine m.gluteus m.iliopsoas functional condition of same students in the end of swimming teaching. During the research, students with low levels of swimming skills were set m. Gluteus maximus and m. Iliopsoas condition after manual therapy techniques [4,5]. The result is a set m.gluteus max. and m.iliopsoas imbalance in 22% cases. During the school year, using a variety of exercises swimming, it was found that the muscle condition is improved by 7%. It can be concluded that the process of swimming training had a positive impact muscle's functional condition. This study can be continued by investigating other muscle groups.