Abstract
Introduction. The analysis of a student’s environment involves a set of stressors in the field of human ecology, including not only genetic but also epigenetic factors.
Material, method. Body posture examinations were carried out in a group of 65 students aged 7, using the moiré projection method in eight positions: 1 – habitual posture, 2 – posture after 10 minutes of pulling a container with school supplies with one hand, 3 – one minute after removing the load, 4 – two minutes after removing the load. Physical fitness was measured using the Sekita test, supplemented with an endurance test. The significance of differences between measurements 1 and 2 was analysed to determine the impact of load and its correlation with physical fitness, to study its impact on the value of differences in body posture features. Conclusions. 1. Transport of school supplies by pulling a container with the left or right hand causes significant changes in the values of selected body posture features of girls and boys. It should be assumed that these changes will be even greater the heavier the weight of the container, the longer the transport time and the greater the intensity of physical effort. Therefore, this method of transporting school supplies by first-grade students should not be recommended. 2. The level of general physical fitness has a diversified impact on the scope of changes in body posture features as a result of the adopted method of transport of school supplies. Among boys, the impact is significant, and among girls only when pulling with the right hand. Taking into account individual abilities, among boys, the value of posture features is affected by speed, power, endurance and agility, and among girls, additionally by strength.

Key words:
backpack, body posture, projection moiré, physical fitness