Modeling the content of physical education classes aimed at the harmonious development of muscle strength, motor coordination, speed-strength abilities, and cardiorespiratory endurance in middle school children

Abstract

The study addresses the issue of achieving harmonious development of muscle strength, motor coordination, speed-strength qualities, and cardiorespiratory endurance in middle school children under the conditions of limited lesson time in physical education. The aim of this work was to provide theoretical justification and experimental verification of a model for the content of lessons based on the principles of the conjugate development of major physical qualities and the consideration of the body’s functional reserves. A longitudinal pedagogical experiment was conducted in three general education schools involving 342 students aged 12-14 years, randomized into control and experimental groups with homogeneous baseline physical fitness indicators. The methods included dynamometry, control exercises for strength and speed-strength qualities, coordination tests (3×10 m shuttle run, Romberg test, etc.), functional tests (Ruffier index, PWC170, 6-minute run, vital capacity) and heart rate variability monitoring; mathematical and statistical data processing was performed using Statistica 12.0 and SPSS 23.0 software packages, applying Student’s t-test, correlation, and factor analysis at a significance level of p 0.05. It was found that, given the initial comparability of the groups, the experimental model ensured a significantly greater increase in speed-strength and coordination indicators (long jump +9,18% vs. 3,19%, shuttle run improvement 7,03% vs. 1,97%, medicine ball throw +17,18% vs. 6,67%) and a more pronounced improvement in the functional state of the cardiorespiratory system (reduction in Ruffier index by 2,31 conventional units, increase in 6-minute run distance by 163,3 m, vital capacity by 355,1 ml). Correlation analysis revealed strengthened relationships between strength, coordination, and endurance components, reduced intragroup variability, and the formation of a more integrated structure of physical fitness. It was concluded that modeling lesson content based on the integration of multidirectional loads is an effective tool for harmonizing the physical development of adolescents and may serve as a basis for modernizing school physical education programs.