What does oxygen supply to the muscles during physical activity?

During physical activity, muscles require a constant and sufficient supply of oxygen to produce energy for sustained performance. The primary energy pathway for muscle activity, particularly during aerobic exercise, relies on oxygen to convert substrates like carbohydrates and fats into adenosine triphosphate (ATP), which is the energy currency of the cell. This process, known as aerobic metabolism, is essential for prolonged activities, such as running, cycling, or swimming, where endurance is required.

Oxygen allows muscles to efficiently generate energy over extended periods, thereby enhancing athletic performance. When oxygen levels are adequate, muscles can maintain their activity without accumulating byproducts like lactic acid, which can lead to fatigue. This is why a steady oxygen supply is critical for optimal energy production during exercise.