149-c : VO2 max, physiology

Oxygen consumption in cyclists increases with increasing speed to a maximum value which can be sustained briefly. The performance in endurance athletes such as cyclists and runners is primarily dependent on the oxygen uptake ability of the cardiovascular system. This ability is the VO2 max

Definition of VO2max

The maximum volume (VAN), oxygen gas (O2) per unit of time that the human body can absorb during physical exertion, measured at sea level. The VO2 max is expressed as the number of milliliters of oxygen per kilogram of body weight per minute (ml / kg / min).

Determination of VO2 max

The VO2 max may be determined in a laboratory, by measuring the oxygen uptake and CO2 emissions during a long-term and increasing exercise test. The VO2 max is reached when the oxygen uptake does not increase, despite an increasing effort.

VO2 max is usually only determined on a treadmill or a bicycle ergo meter. The determination of the VO2 max should be carried out under medical supervision.

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VO2max: to increase the intensity of the effort oxygen uptake will not increase.

Methods to determine the VO2 max:
The respiration measurement may be carried out both on a treadmill as on a bicycle ergo meter. From the maximum power in watts, that is achieved at the test on the bicycle ergo meter, the VO2 max can be derived through a formula.
Because the treadmill test and the cycle test are laborious, a number of methods have been developed to estimate the VO2 max.

Simple crude method to predict VO2max:
On the basis of HRmax and the HRrest
Formula: VO2 max = 15 x (HRmax / HRrest)

Second method is the Cooper test:
Determine the distance a person can run in 12 minutes. With that distance, the VO2 max can be calculated.
Formula: VO2 max = (d -505) 45
d = distance in meters in 12 minutes.

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Respiratory measurement on bicycle ergo meter
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and treadmill

Third method for determining the maximum power in Watts on a bicycle ergo meter:

Formula: VO2 max = (395 + 11.3W) / m

m: weight in kilograms.
W is the maximum wattage that is reached during the test cycle.

VO2 max is dependent on:

  • Genetic predisposition: ‘if you want to be a great cyclist, choose your parents carefully.
  • Gender: the VO2 max in men is 10 to 15 percent higher than in women.
  • Age: the VO2 max decreases by 0.5 to 1.0 percent from the age of 35.
  • Training: the VO2 max may rise 10 to maximum 30 percent.
  • Weight: Losing weight leads to a higher VO2 max.

VO2 max of cyclists of world level is about 88 ml / kg / minute. Elite riders like Froome and Nibali can achieve these values by their innate talent combined with years of training. Ordinary people with average values for their VO2 max will never reach the level of the great riders. Even with the most sophisticated and fanatical training that is impossible.

That means that the VO2 max in untrained state already has to be pretty high. VO2 max can rise through training only up to 30 percent. If you want to achieve by training the level of Froome and Nibali your untrained VO2 max value has to be 62.

Above the age of 35 the VO2 max will decline, in untrained people, with one percent per year. Through training, this decline can be limited to 0.5 percent per year.

MEN:  VO2 max  ml/kg/min

AGE Very bad Bad Reasonable Good Very Good Exellent
AGE 13 - 19 <35.0 35.0-38.3 38.4-45.1 45.2-50.9 51.0-55.9 >55.9
AGE 20 - 29 <33.0 33.0-36.4 36.5-42.4 42.5-46.4 46.5-52.4 >52.4
AGE 30 - 39 <31.5 31.5-35.4 35.5-40.9 41.0-44.9 45.0-49.4 >49.4
AGE 40 - 49 <30.2 30.2-33.5 33.6-38.9 39.0-43.7 43.8-48.0 >48.0
AGE 50 - 60 <26.1 26.1-30.9 31.0-35.7 36.8-40.9 41.0-45.3 >45.3
AGE 60+ <20.5 20.5-26.0 26.1-32.2 32.3-36.4 36.5-44.2 >44.2

WOMEN: VO2 max  in ml/kg/min

AGE Very bad Bad Reasonable Good Very Good Exellent
AGE 13 - 19 <25 25.0-30.9 31.0-34-9 35.0-38.9 39.0-41.9 >41.9
AGE 20 - 29 <23.6 23.6-28.9 29.0-32.9 33.0-36.9 37.0-41.0 >41.0
AGE 30 - 39 <22.8 22.8-26.9 27.0-31.4 31.5-35.6 35.7-40.0 >40.0
AGE 40 - 49 <21.0 21.0-24.4 24.5-28.9 29.0-32.8 32.9-36.9 >36.9
AGE 50 - 60 <20.2 20.2-22.7 22.8-26.9 27.0-31.4 31.5-35.7 >35.7
AGE 60+ <17.5 17.5-20.1 20.2-24.4 24.5-30.2 30.3-31.4 >31.4

In the mountains the air pressure and therefore the VO2 max decreases with height. On the summit of Mount Everest, 8850 meters high, is the VO2 max only 27% of the value at sea level. If ordinary people with an average VO2max of 40 ml / kg / min climb Mount Everest  their VO2 max will decline to 10.8 ml / kg / min, barely enough to survive. Without supplemental oxygen at this altitude mountaineers can barely pass 50 meters per hour.

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Mount Everest, 8850 meters high. On sea level the VO2 max is 73% higher.

The relationship between VO2 max and performance in running and cycling.

VO2 max corresponds to the maximum power that you can sustain about 10 minutes. With a shorter exercise time a greater power can be supplied because of the contribution of the anaerobic system. If the exercise time is increased to 10 minutes, then the power slowly decreases again.

Using the VO2 max one can calculate exactly what times and speeds are possible during running and cycling, at various distances. Later we come back to that. Here already some possibilities:

How fast can you go at a certain VO2max?
Running: V = 0.280 x VO2max
Speeds climb cycling: Vv = 0.030 x VO2max

Athlete with a VO2max = 55.4 mL / kg / min

V = 0.280 x 55.4 = 15.5 km/h (running)
Vv = 0.030 x 55.4 = 1.66 km/h (vertical speed cycling)

NOTE: It is maximal speeds for 10 minutes.

Some antelopes have a VO2max of 300 ml / kg / min. Without any problems they can maintain a speed of over 60 km per hour. Greyhounds and thoroughbred horses also have very high VO2 max values. Respectively 90 and 150 ml / kg / min. Much higher than human elite athletes.

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Antelopes have a VO2 max of 300 ml/kg/min.