Abstract. In this article, when planning the training loads of 12-13-year-old weightlifters at the initial training stage, the age-specific characteristics, i.e., the sensitive periods of the development of physical qualities and the age-specific natural development of movement skills, are taken into account. By determining the optimal proportions of training tools, it was achieved to increase the indicators of physical development and the level of physical training in 12-13-year-old weightlifters. In assessing the level of children's physical preparation and physical development, it was achieved not to increase the number indicators, but to prevent excessive load on the body.