What is a common indicator of cardiorespiratory fitness?

VO2 Max is considered the gold standard for measuring cardiorespiratory fitness, which reflects the maximum amount of oxygen that an individual can utilize during intense exercise. This metric directly indicates how well the cardiovascular and respiratory systems are functioning together to supply oxygen to the muscles. The higher the VO2 Max, the more efficient the body is at transporting and using oxygen, which correlates with greater aerobic endurance and overall fitness levels.

While heart rate, blood pressure, and lung capacity are also important indicators of health, they do not specifically measure the capacity for sustained physical activity in the same way VO2 Max does. Heart rate may fluctuate based on numerous factors including fitness level and stress, while blood pressure is more about the force of blood against vessel walls, and lung capacity assesses the volume of air one can inhale and exhale but does not directly quantify the efficiency of oxygen usage in the body during exercise.