Overexertion injuries are found to be a major cause of difficulties both at the level of professional and amateur sports, as well as in activities of daily life. This paper is based on the prevention of overexertion injuries by developing muscle strength. Also, great importance is attached to the ability of timely eccentric muscle contraction. In addition to developing the three basic types of muscle strength, i.e. static, repetitive and maximal, functional strength is also explained as a concept and the goal of development itself. The types of muscle contractions are clarified, as well as their differentiation in examples of movements and exercises. Furthermore, the differences between motor abilities, that is, physiological adaptations of strength and power, and their importance in the prevention of injuries and overexertion syndrome, are listed and explained. As a concrete approach to developing muscle strength, several possible principles of developing strength through different planning and programming of training processes in the form of tissue adaptation to certain levels of stress have been highlighted. The process of preventing injury and overexertion syndrome through various progressive phases of muscular endurance, maximum strength, power and specific and functional movements is also exemplified.