CSSD Practice Exam 2026 – Complete Study Resource

The typical VO2max range for optimal fatty acid oxidation is indeed around 60-65%. At this range, the body is able to efficiently utilize fat as a primary source of fuel during prolonged exercise. This is due to the fact that fat oxidation becomes more favorable at moderate intensities when there is sufficient oxygen availability for aerobic metabolism.

At lower intensities, the body may rely more on carbohydrates, but as the exercise intensity and VO2max increase, the proportion of energy derived from fat increases until reaching an optimal point. Beyond this range, particularly at high intensities, carbohydrate breakdown becomes the dominant energy pathway, which decreases the reliance on fatty acid oxidation.

This physiological understanding reflects how the body transitions between utilizing carbohydrates and fats during different intensities of exercise and helps to underscore why training in this VO2max range can improve overall endurance and fat metabolism efficiency during physical activity.