Physical capacity is not an inherent human quality. It is formed, developed and improved. It is achieved with a systematic and well-chosen training routine, which can lead to quantitative and qualitative changes in human capabilities when performing motor actions in a particular environment. The purpose of the present study is to analyze the results of the studied indicators of physical performance of 9-year-old students for a 12-year period (2007-2019). The subjects are 9-year-old students, distributed in equal numbers – 50 in four groups, subjected to testing every 4 years during the school years 2007/2008, 2011/2012, 2015/2016 and 2019/2020. The survey was conducted at the beginning of each school year. The following methods are applied to solve the problems and achieve the goal of the experiment: 1. Testing – includes 5 indicators for measuring physical capacity. 2. Mathematical-statistical methods – Variation, comparative and graphical analysis are used. The results obtained from the variation analysis are presented in tabular and graphical form. Tables 2-5 show the achievements after statistical processing of the data taken by means of tests carrying information about the physical capacity of 9-year-old students during the 12-year period, and Figures 1 and 2 show the variability of the studied indicators for different periods of time. Despite that, main conclusion of the study is that the physical capacity of 9-year-old students in 2019 is significantly improving. The tendency to observe a sedentary lifestyle, obesity and reduced physical activity in students is refuted by the present experiment. With regard to the first two indicators characterizing the explosive power of the lower and upper limbs, it can be summarized that in 2019 the average values in the test “Long jump from a place with two legs” have significantly increased, and in the indicator “Throwing a solid ball”, the results have significantly decreased. For the other three indicators, determining the speed, endurance and flexibility of the surveyed students, it is found that the average values in 2019 are much better in comparison to those of the surveyed students in preceding periods. Research shows that the four samples for the period 2007-2019 are relatively homogeneous in all indicators of physical capacity.