The evolution of endurance development paradigms is considered: from the classical model of continuous load to the justification of modern high-intensity interval methods. The issue of developing general endurance occupies a central place in the theory of physical education and the methodology of health-saving technologies during the late 20th and early 21st centuries. Historically, the dominant paradigm during the previous century was the method of continuous load of low and moderate power. This model was based on extensive accumulation of volumes, which was considered the only safe way to adapt the cardiovascular, muscular and other systems of the body. However, fundamental research in the field of biochemistry, physiology, and genetics of muscle activity forced to reconsider these views. The Ukrainian biochemist Olga Chepinoga played a pioneering role in the formation of the scientific basis of endurance. Back in 1939–1940, she presented the world's first evidence that training induces mitochondrial biogenesis in skeletal muscle. Her work on the activity of dehydrogenases during training and fatigue laid the foundation for understanding how physical activity transforms the energy potential of the cell at the molecular level, but her scientific legacy has not been sufficiently studied. The traditional methodology of the continuous load technique is viewed through the prism of classical physiology, in particular: expansion of the heart chambers and development of the capillary network. At the same time, modern high-intensity interval techniques, based on short bursts of physical activity (85–95% of the maximum heart rate), activate the same molecular signaling pathways as many hours of training. The key advantage of high-intensity interval training is its time efficiency and powerful metabolic response, which makes it ideal for improving the health of a wide range of populations. A retrospective analysis of the above problem shows a change in the vector of research: from the study of mechanical volume accumulation to the analysis of cellular adaptations, the origins of which lie in the works of representatives of the Ukrainian biochemical school. The article justifies the need to synthesize the historical experience of «basic endurance» with innovative high-intensity protocols to create safe and effective health programs. We have defined the selected topic as the goal of the review study. The literature search was carried out based on keywords in the electronic databases PubMed and SPORTDiscus.

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