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The maximum oxygen intake indicates how much oxygen the body can absorb and consume per minute during maximum effort. It is a key performance indicator in endurance sports.

VO2max, or maximum oxygen intake, is the highest amount of oxygen that the body can absorb and consume during physical activity. The higher the VO2max, the better the performance in endurance sports. 

Top athletes can achieve VO2max values of over 90 ml/kg/min, while the values for the general population are significantly lower. For men aged 40 to 49 years, a VO2max above 46.4 ml/kg/min is considered excellent, while for women in the same age group values above 39.7 ml/kg/min are considered extremely good. 

Factors that affect VO2max

VO2max is largely genetic and gradually decreases from the age of around 30. Through training, it can be improved by about 15 to 20%. The ability to make full use of a high percentage of VO2max (over a longer period of time) without lactate accumulation is the key to performance. Training must therefore be tailored accordingly.

VO2max can be positively influenced by the following measures:

• Interval training: Interval training increases oxygen intake and blood circulation to the muscles. 
• Threshold training: Longer speed sessions just below the anaerobic threshold improve the ability to buffer lactate and use oxygen efficiently.
• Long endurance sessions: These do not directly boost VO2max, but indirectly improve heart performance, muscle circulation and mitochondrial activity, which are considered powerhouses for the cells as they produce ATP. All of this leads to a higher oxygen intake in the long term.
• Altitude training: Spending time at altitude leads to increased production of red blood cells and improves oxygen transport.
• Strength training: Maximum strength training can improve running economy and reduce oxygen consumption per exercise session.
• Consistency: Consistent endurance training over years with a long-term increase in intensity and scope increases blood circulation in the muscles and the density of the mitochondria in the muscle cells.

Training to improve VO2max

To increase VO2max, it is important to combine long endurance sessions with high-intensity workouts. The anaerobic sessions push the body to its limits and promote changes that optimise oxygen utilisation. Effective training methods include:

• Classic VO2max intervals: 4-6 x 3-5 minutes at 90-95% of your maximum heart rate with the same recovery time.
• In and Outs: Very short, high-intensity intervals (e.g. 8-10 x 20 seconds with 10-second rest while walking slowly, 1 to 3 sets with 5 minutes break).
• Longer speed runs: 30-40 minutes just below the anaerobic threshold.

VO2max training should only be carried out in a healthy condition. To ensure complete adaptation, it should be supplemented with recovery runs, speed runs and long, easy runs. Due to the high physical effort, rest days or light sessions should be planned between the intensive workouts.

How best to include intensive sessions in a training week:

• Monday: Easy endurance run (45-60 mins) or rest day
• Tuesday: VO2max intervals – 5 x 3 mins at 90-95% of your maximum heart rate with 3-min rest while walking slowly
• Wednesday: Recovery run (30 mins) + strength training
• Thursday: Easy endurance run (40 mins) 
• Friday: Day of rest
• Saturday: Speed run – 20-30 mins at 80-90% of your maximum heart rate
• Sunday: Long jog (75-90 mins at a relaxed pace)