Background: In recent years, due to the rapid development of digital technology and the decline in physical activity, there has been a noticeable decrease in the physical development of children and adolescents, along with an increased risk of non-communicable diseases. Organizations such as the World Health Organization, UNESCO, and the International Olympic Committee recommend integrating regular physical activity into daily life to promote population health. Therapeutic physical exercise is an effective method for restoring bodily functions, increasing muscle strength, and correcting movement impairments, and it serves as an important tool for supporting the physical development and health of school-aged children. Therefore, this study aimed to determine the effects of therapeutic physical exercise on the physical development indicators of children with chronic illnesses and disabilities. Aim: To determine the impact and effectiveness of inclusive participation of students with pathological conditions in physical education classes on their physical development and health indicators. Materials and Methods: Thirty students diagnosed with chronic diseases and enrolled in general education schools participated voluntarily. At the beginning of the study, demographic information was collected, and baseline measurements were taken to assess flexibility, waist and hip circumference, forearm and back muscle strength. Therapeutic exercises tailored to the characteristics of each condition were then implemented according to the FITT principle. After the intervention period, follow-up measurements were conducted. Data were analyzed using descriptive statistics, paired t-test, independent t-test, Pearson correlation, and Cohen’s d in SPSS 25.0 software. Statistical significance was evaluated at the p<0.05 level. Results: After the therapeutic exercise intervention, participants’ flexibility increased by 3.70 cm, right-hand muscle strength by 7.50 kg, left-hand muscle strength by 6.92 kg, and back muscle strength by 17.60 kg, all of which were statistically significant changes (p<0.05). Height increased by 2.36 cm and weight by 1.98 kg. The effect sizes of these indicators ranged from moderate to high. Conclusions 1. The results of this study demonstrate that therapeutic exercise may produce statistically significant positive changes in certain physical fitness parameters among students with pathological conditions, particularly in upper limb and back muscle strength, as well as flexibility. The observed effect sizes ranged from moderate to high, indicating potential practical significance for implementation in practice. 2. In contrast, the changes observed in height and body weight are considered to reflect the indirect effects of therapeutic exercise together with the participants’ natural physiological growth and development. 3. This study suggests that therapeutic exercise may serve as an effective approach for promoting inclusive participation in educational activities among students who are exempted from regular physical education classes, while also supporting the improvement of their physical capacity.

Introduction: Factors such as social and economic conditions, technological development, modern urbanization, lifestyle, physical activity, nutrition, and air pollution affect physical growth and development. Aim: To study the physical development of Mongolian children. Objectives: 1. To measure the physical indices (weight, height) of children aged 6-17 years old with some influencing factors. Material and method: Using a random sampling method, children's body height and weight were examined at a particular point in time using widely accepted methods. Statistical analysis was performed using the "SPSS ver.25" program. Result: The growth of children's height and weight is progressing according to general patterns of age and gender. Girls grow rapidly between the ages of 10-13 and stabilize after wards, while boys a sharp growth spurt between the ages of 13-17, with the average height of 17-year-old boys being 171.44 cm and 160.25 cm for girls, which is slightly higher than previous studies (Otgon G, 2006, Munkhzaya M, 2020). The trend of weight growth is more prominent in boys. However, compared to international standards (Russia, WHO, CDC), our children's height and weight are lower. The statistics show that parental education, income, exercise, and living environment positively influence growth and development, whereas excessive television watching and air pollution negatively affect it (p< 0.05). Conclusion 1. Children's growth is normal, but observed increase of the body weight of boys. Having healthy and well educated parents, as well as engaging in physical activity positively influences children's height. A lack of physical activity negatively affects height and increases weight. Mongolian children are shorter and lighter compared to foreign children (from Russia and America - CDC).