VO2 Max and Lactate
Testing in San Diego

A key parameter for marathon and ultra-distance athletes. Oxygen is actively delivered to muscle cells during movement, breaking down fats and carbohydrates for energy. If the exercise intensity is too high, oxygen supply to the muscles is disrupted, slowing fat metabolism and leading to lactate accumulation. The aerobic threshold marks the point beyond which lactate in the blood increases even if exercise intensity remains unchanged. Exceeding AeT shifts metabolism to carbohydrate breakdown while inhibiting fat burning.

A crucial physiological marker reflecting fitness level. The higher the anaerobic threshold, the better-trained an athlete is, with a more developed aerobic energy system capable of operating at 80-95% of VO2 max. The anaerobic threshold occurs at a higher heart rate than the aerobic threshold and corresponds to a lactate concentration of 4 mmol/L, marking the transition from aerobic to anaerobic energy production. Athletes with a higher AnT can sustain faster race paces over 30-90 minutes, while less-trained athletes reach their AnT at lower intensities. AnT is especially important for running distances from 5 to 21 km, short- to mid-distance cycling races, and ski racing. The higher the AnT, the faster an athlete can maintain their pace over a race distance.

VO2 max represents the maximum amount of oxygen the body can utilize per minute and indicates the capacity of the oxygen transport system. It is closely related to heart performance and muscle oxygen utilization. For beginner athletes, VO2 max training should be approached cautiously, as maintaining VO2 max pace is possible for only a few minutes. For athletes competing in events lasting longer than 8-10 minutes, VO2 max is less directly tied to performance.

Different training zones produce different effects, making it essential to individualize them. Endurance sports typically recognize five training zones. Low-intensity zones develop basic endurance, while zones 4 and 5 enhance speed and anaerobic endurance.