Muscle strength is one of the most important elements of fitness that must be available to football players. For a long period of time the weight training has been the subject of controversy among the specialists in the preparation and training of football players, the scientific researches has settled this controversy, where most of the results indicated that weight training has become necessary for the development of different types of muscular strength (maximum force – the special force of speed – endurance power). In fact the Algerian football sport lacks weight training programs and how to plan and evaluate the level of development of muscular strength during the training program with scientific bases and methods to avoid muscle inflation and increase muscle mass that can affect skill performance. The researchers' study note that there is a great detour of football players around the muscle strengthening rooms without a formal training program, which may lead to an increase in muscle inflation. So that the researchers decided to design a weight training program ,and diagnosing the percentage of progression and its relation to the dynamics of muscle strength development of different muscle groups and increasing muscle inflation as much as required for football players under 21 years of research experimental sample.