This report provides a comprehensive overview of the body's response to acute exercise, detailing the effects on various physiological systems. It begins by exploring the musculoskeletal system, highlighting how exercise influences blood supply, muscle pliability, range of movement, and muscle fiber micro-tears. The report then delves into the energy systems, including phosphocreatine, lactic acid, and aerobic systems, and their roles in providing energy during exercise. Furthermore, it examines the cardiovascular and respiratory responses, such as anticipatory rise, blood pressure changes, vasodilation, breathing rate, and tidal volume. The report emphasizes the interconnectedness of these systems, illustrating how they work together to support physical activity. Finally, the report references studies on the effects of exercise on brain-derived neurotrophic factor, providing a well-rounded understanding of the body's reaction to acute exercise.