What does the utilization theory propose about VO2 max?

The utilization theory posits that VO2 max, which is the maximum rate of oxygen consumption measured during intense exercise, is fundamentally determined by the body's ability to utilize the oxygen that is available at the cellular level. This means that even if the body is capable of delivering a certain amount of oxygen through the cardiovascular system, the effectiveness with which the muscles can use that oxygen for energy production is critical.

At the cellular level, this involves various factors including the efficiency of the oxidative metabolic pathways, the density of mitochondria within muscle cells, and the capability of the muscles to extract and utilize oxygen from the blood. This theory emphasizes that it is not just the capacity of the heart and lungs to pump and circulate oxygen that defines VO2 max, but also how effectively the muscles can leverage that oxygen for aerobic metabolism.

In contrast, while muscle strength and endurance play roles in overall fitness, they are not the primary determinants of VO2 max according to this theory. Similarly, relying solely on cardiovascular fitness overlooks the cellular mechanisms involved in oxygen usage, and focusing on external environmental factors does not align with the physiological processes described by utilization theory.