This article reflects the experimental argumentation of the effectiveness of applying the experimental program for the development of muscle strength to 16-17 years-old rugby players in an annual training cycle. Starting from the hypothesis that the use of weight training exercises for strength development, systematized depending on the stage of preparation of the 16-17 years old rugby players in the sport training, will directly influence the full potential of their muscular force, so the experimental program was developed and proposed to experimental group, which reflects: objectives specific to the training meso-cycle, connection ratio between effort and rest, dosing the means of force development in a training lesson, while the control group followed the traditional training in gym. In both groups were selected and analysed the tested indices for determining the maximum force at the beginning and the end of the pedagogical experiment, the data being mathematically and statistically processed and presented in tabular form. Analysing the final results, we can see that the hypothesis advanced at the beginning of the researches has been confirmed, which has allowed to raise the maximum potential of the muscular force through the use of weight training exercises for the development of force, systematized depending on the stage of preparation of the 16-17 years old rugby players in the training process.