What is VO2 max?

VO2 max is a factor that can determine an athlete’s capacity to perform sustained exercise and is linked to aerobic endurance. VO2 max refers to the maximum amount of oxygen that an individual can utilize during intense or maximal exercise. It is measured as “milliliters of oxygen used in one minute per kilogram of body weight.”

V02 max is generally considered the best indicator of an athlete’s cardiovascular fitness and aerobic endurance.

An athlete with a high VO2 max has a healthy heart, lots of oxygen carrying red blood cells, a great number of capillaries, as well as numerous mitochondria (known as the “powerhouses of the cell”) to process oxygen and lots of enzymes to help carry away waste products(mitochondria) which cause fatigue.

VO2 Max testing (Clinical)

VO2 max Test

VO2 max can be determined through a number of physical evaluations. Testing requires sophisticated equipment to measure the volume and gas concentrations of inspired and expired air. There are many protocols used on treadmills, cycle ergometers and other exercise equipment to measure VO2 max directly. Workloads are gradually increased from moderate to maximal intensity while oxygen consumption (VO2) and carbon dioxide output (VCO2) are calculated. Results are measured in ml/kg/min.

An athlete is hooked up to a computer and breathes into an apparatus that analyses exhaled air while he runs on a tread mill. The athlete warms up with 5-10 minutes of easy treadmill running. At that point, the treadmill belt increases speed every minute or two. Once the athlete can’t keep up with the treadmill speed, he or she lets the tester know to end the test.

During a VO2 max test, a special mask is worn which allows a runner to breathe in room air through a one-way valve. When a athlete exhales, air flows out the other side of the mask and into a gas-analysis machine. Through various mechanisms, the total amount of air exhaled plus the exact amount of oxygen, carbon dioxide, and nitrogen are determined. The very highest amount of oxygen consumed per minute during the test becomes “VO2 max.”

Field Testing for VO2 max

The Cooper Endurance Test (Dr. Kenneth Cooper, author of “Aerobics”) is to help you determine VO2 max with reasonable accuracy, and without the need of expensive equipment. A more accurate test might cost you hundreds of dollars, and this is good enough for the purpose of determining roughly in how good shape is your oxygen processing capacity.

VO2 max is defined as the maximum amount of oxygen that your body can take in, deliver, and use in one minute. It is limited both by the amount of oxygenated blood the lungs and circulatory system can process, and by the amount of oxygen the muscles can extract from the blood. It is estimated that VO2 max goes DOWN about 1% per year. The fall in marathon performance is known to be about 13% per decade.

This makes VO2 Max a critical sign of aging, and it is one we can measure… and reverse somewhat with proper aerobic training. To do this, Dr. Cooper advises that you must raise your heart rate to between 65 and 85 percent of its maximum, through walking or running or swimming or bicycling or other aerobic exercise for at least 20 minutes, three to five times a week.


To Take This Test You Will Need:

  • 400 meter track – marked every 100 meters
  • Stop Watch

The test consists of seeing how far you can run/walk in twelve minutes. Record the total distance covered to the nearest 100 meters.

The following formula will give you a reasonable and inexpensive approximation of your numerical Vo2 max. This formula was derived by correlating the actual VO2 MAX of athletes and the maximum distance which they could run in 12 minutes:


(Distance covered in meters, minus 504.9) / 44.73

Do not even attempt this test unless you have been running and training beforehand, and you know you can run 2 miles without stopping. Start by trying to walk 2 miles fast, then run 1 mile slow, then speed up, and increase the distance until you can, perhaps, run 2 miles slowly. Heart rate should not exceed 220 minus age.

The tables below list VO2/Kg in ml/min/kg for men and women in a range of ages and levels of fitness.

Female (values in ml/kg/min)


Very Poor








25.0 – 30.9

31.0 – 34.9

35.0 – 38.9

39.0 – 41.9




23.6 – 28.9

29.0 – 32.9

33.0 – 36.9

37.0 – 41.0




22.8 – 26.9

27.0 – 31.4

31.5 – 35.6

35.7 – 40.0




21.0 – 24.4

24.5 – 28.9

29.0 – 32.8

32.9 – 36.9




20.2 – 22.7

22.8 – 26.9

27.0 – 31.4

31.5 – 35.7




17.5 – 20.1

20.2 – 24.4

24.5 – 30.2

30.3 – 31.4


Male (values in ml/kg/min)   


Very Poor 








35.0 – 38.3 

38.4 – 45.1 

45.2 – 50.9 

51.0 – 55.9 




33.0 – 36.4 

36.5 – 42.4 

42.5 – 46.4 

46.5 – 52.4 




31.5 – 35.4 

35.5 – 40.9 

41.0 – 44.9 

45.0 – 49.4 




30.2 – 33.5 

33.6 – 38.9 

39.0 – 43.7 

43.8 – 48.0 




26.1 – 30.9 

31.0 – 35.7 

35.8 – 40.9 

41.0 – 45.3 




20.5 – 26.0 

26.1 – 32.2 

32.3 – 36.4 

36.5 – 44.2 


Table Reference: The Physical Fitness Specialist Certification Manual, The Cooper Institute for Aerobics Research, Dallas TX, revised 1997 printed in Advance Fitness Assessment & Exercise Prescription, 3rd Edition, Vivian H. Heyward, 1998.

Improving Your VO2 max

One can improve VO2 max in several ways. First looking at the equations you can improve your VO2/Kg simply by losing weight, assuming you lose fat and not muscle. Women are at a slight disadvantage because they have a higher percentage of essential body fat.

If you want a high VO2 max, choose your parents carefully. One group of scientists concluded that heredity determines up to 50 percent of your endurance ability. Still, that leaves 50 percent that can be influenced by training.

Secondly would be to increase heart rate. There is not much that can be done to increase max heart rate. In fact it decreases with age. We can increase the cardiac output by making the heart larger and stronger. This can be achieved over the years through prolonged endurance training. A trained athlete’s resting heart rate is lower because it pumps more blood per beat than an untrained person’s does.

The last parameter in the equation is the body’s ability to extract more oxygen out of the arterial blood. This is increased mainly as a result of long, slow endurance runs. The aerobic capacity of Type I fibres (slow-twitch muscle) is improved only after 1.5 hours of exercise.

Per-Olof Astrand, MD, PhD, a pioneer in the field of work physiology, with his research focusing on the oxygen transport system in humans suggests several ways to improve oxygen uptake.

The following are samples of Astrands workouts for improving oxygen uptake:

  • (1) – Run at maximum speed for 5 minutes. Note the distance covered in that time. Let us assume that the distance achieved is 1900 metres. Rest for five minutes, and then run the distance (1900 metres) 20% slower, in other words in six minutes, with 30 seconds rest, repeated many times. This is equal to your 10 Km pace
  • (2) – Run at maximum speed for four minutes. Note the distance covered in that time. Rest for four minutes. In this case, we will assume you run a distance of 1500 metres. Now run the same distance 15% slower, in other words in 4 minutes 36 seconds, with 45 seconds rest, repeated several times. This approximates to a time between the athlete’s 5 Km and 10 Km time
  • (3) – Run at maximum effort for three minute. Note the distance covered in that time. The distance covered is, say 1000 metres. Successive runs at that distance are taken 10% slower or at 3 minutes 18 seconds, with 60 seconds rest, repeated several times. This approximates to your 5 Km time
  • (4) – Run at maximum effort for five minutes. Note the distance covered in that time. The distance covered is 1900 metres. Rest five minutes. The distance is now covered 5% slower with one and a half minutes rest. This is approximately 3K pace for you, i.e., five minutes 15 seconds/1900 metres
  • (5) – Run at maximum effort for three minutes. The distance covered is 1100 metres. When recovered, the athlete then runs the same distance 5% slower, i.e., three minutes nine seconds/1100 metres, with one minute rest, repeated several times. This is at 3 Km pace

When and how often

It is suggested that in the winter sessions (1) and (2) are done weekly, and in the track season sessions (3), (4) and (5) are done weekly by runners from 800 meters to the half-marathon. Although it would be convenient to use the original distance marks made by the duration efforts, this does not take into account the athlete’s condition before each session, so the maximum effort runs must be done on each occasion when they may be either more or less than the previous distance run. The maximum duration efforts are in themselves quality sessions. If the pulse rate has not recovered to 120 beats per minute in the rest times given, the recovery period should be extended before the repetitions are started. The recovery times between the reps should be strictly adhered to. These workouts make a refreshing change from repetition running. When all five sessions are completed within a month, experience shows substantial improvements in performance.