VO2 max

VO₂ max

 

 maximal oxygen consumption,

 maximal oxygen uptake,

 aerobic capacity.

 the maximum capacity of an individual's body to transport and utilize oxygen during incremental exercise, which reflects the physical fitness of the individual.

The name is derived from

V̇ - volume per time, O₂ - oxygen, max - maximum.

 

VO₂ max is expressed either

as an absolute rate in litres of oxygen per minute (l/min) or

as a relative rate in millilitres of oxygen per kilogram of bodyweight per minute (ml/kg/min), the latter ｅxpression is often used to compare the performance of endurance sports athletes. A less size-biased measure is to divide by rather than mass.

 Measuring VO₂ max

Accurately measuring VO₂ max involves a physical effort sufficient in duration and intensity to fully tax the aerobic energy system. In general clinical and athletic testing, this usually involves a graded exercise test (either on a treadmill or on a cycle ergometer) in which exercise intensity is progressively increased while measuring ventilation and oxygen and carbon dioxide concentration of the inhaled and exhaled air. VO₂ max is reached when oxygen consumption remains at steady state despite an increase in workload.

 Fick Equation

VO₂ max is properly defined by the Fick Equation:

, when these values are obtained during an exertion at a maximal effort.

where Q is the cardiac output of the heart, CaO₂ is the arterial oxygen content, and CvO₂ is the venous oxygen content.

 Cooper test

Dr. Kenneth H. Cooper conducted a study for the United States Air Force in the late 1960s. one of the results of this was the Cooper test in which the distance covered running in 12 minutes is measured. An approximate estimate for VO₂ max (in ml/min/kg) is:

where d₁₂ is distance (in metres) covered in 12 minutes. There are several other reliable tests and VO₂ max calculators to estimate VO₂ max.

 VO₂ max Levels

“Maximal oxygen uptake (VO₂max) is widely accepted as the single best measure of cardiovascular fitness and maximal aerobic power. Absolute values of VO₂max are typically 40-60% higher in men than in women.”^[1] Clearly, then, VO₂max varies considerably in the population, with sex being a primary determining factor in this variability.

The average young untrained male will have a VO₂ max of approximately 3.5 litres/minute and 45 ml/kg/min.^[2] The average young untrained female will score a VO₂ max of approximately 2.0 litres/minute and 38 ml/kg/min.^{[citation needed]} These scores can improve with training and decrease with age, though the degree of trainability also varies very widely: conditioning may double VO₂max in some individuals, and will never improve it at all in others.^[3][4]

In sports where endurance is an important component in performance, such as cycling, rowing, cross-country skiing, swimming and running, world class athletes typically have high VO₂ maximums. World class male athletes, cyclists and cross-country skiers typically exceed 75 ml/kg/min and a rare few may exceed 90 ml/kg/min for men and 70 ml/kg/min for women.^{[citation needed]} Three time Tour de France winner Greg LeMond is reported to have had a VO₂ max of 92.5 at his peak - one of the highest ever recorded, while cross-country skier Bjørn Dæhlie measured at an astounding 96 ml/kg/min.^[5] It should also be noted that Dæhlie's result was achieved out of season and that physiologist Erlend Hem who was responsible for the testing stated that he would not discount the possibility of the skier passing 100 ml/kg/min at his absolute peak. By comparison a competitive club athlete might achieve a VO₂ max of around 70 ml/kg/min.^[2] World class rowers are physically very large endurance athletes and typically do not score as high on a per weight basis, but often score exceptionally high in absolute terms. Male rowers typically score VO₂ maximums over 6 litres/minute, and some exceptional individuals have exceeded 8 l/min.

To put this into perspective, thoroughbred horses have a VO₂ max of around 180 ml/min/kg. Siberian dogs running in the Iditarod Trail Sled Dog Race sled race have VO₂ values as high as 240 ml/min/kg.^[6]

 Estimation of VO₂ max

Tests measuring VO₂ max can be dangerous, as any problems with the respiratory and cardiovascular systems will be greatly exacerbated. Indeed many organised VO₂ max tests require a medic to be present. Hence many protocols for estimating VO₂ max have been developed. These generally are similar to a VO₂ max test, but do not reach the maximum of the respiratory and cardiovascular systems and are called sub-maximal tests.

 

 

 

최대 산소 섭취량 [maximal oxygen uptake : V O2 max]

개인의 체력수준은 운동강도를 결정하는 중요한 요소일 뿐만 아니라 개인의 건강상태를 평가함에 있어 유용한 지표가 된다. 

개인의 체력수준을 평가함에 있어 특히 중요시되는 것이 심폐기능에 관한 요소이며

이러한 심폐기능을 평가하는 주요 지표로는 최대산소섭취량을 들고 있다.

최대산소섭취량(maximal oxygen uptake : VO2 max)은 인간이 해수면 수준에서 운동을 수행할 때 섭취할 수 있는 산소량의 단위시간당 최대치를 의미하는 것으로서 산소운반능력과 최대유산소능력에 대한 유용한 정보를 제공한다.

최대산소섭취량이라고 하는 용어를 누가 언제부터 사용했는가는 명확하지는 않지만 이 용어가 세계적으로 알려지게 된 것은 Robinson의 논문에 의해서라고 한다. 1937년에 Robinson 등이 전신지구성 능력이 우수하다고 생각되는 장거리선수의 VO2 max가 일반인과 비교해서 높다는 것을 밝혀낸 이후 최대산소섭취량은 전신지구성 특히 심폐기능의 활동수준의 높이를 나타내는 지표로서 무엇보다 유효하다 것이 인정되어 왔다.

호흡순환계 기능의 통합된 지표로 생각되고 장시간에 걸쳐 운동을 계속하는데 필요한 전신성 지구력을 반영하는 가장 객관적인 지표로서 세계적으로 널리 이용되어 오고 있는 최대산소섭취량에는

1)절대치의 최대산소섭취량(l/min)

2)단위체중당 최대산소섭취량(ml/kg/min)

3)제지방체중당 최대산소섭취량(ml/FFW/min)이 있다.

절대치 최대산소섭취량과 상관관계가 높은 변인은 연령, 체중, 신장, 제지방체중 등이고

단위체중당 최대산소섭취량과 상관관계가 높은 변인은 체중, 체지방률(%fat), 제지방체중이며

제지방체중당 최대산소섭취량과 상관관계가 높은 변인은 연령, 체중, 신장, 절대치 및 단위체중당 최대산소섭취량이다.

신체활동에 의해 변화되는 VO2 max에 영향을 미치는 요인은 근육량, 순환계, 호흡계, 모세혈관계 및 체지방량 등이다.

VO2 max가 높다는 것은 전신지구성 운동능력이 높다는 것을 의미하는데, 마라토너 이봉주선수의 최대산소섭취량(1분간 공기중의 산소를 섭취할 수 있는 능력)은 체중 1kg당 78.6 리터로 세계 톱클레스 마라토너와 같은 수준을 기록하고 있다.

일반 남자 성인에서 체중당 최대산소섭취량이

20대 미만(54.3 이상),

20대(60.0 이상),

30대(55.3 이상),

40대(45.5 이상),

50대 이상(42.9 이상)이면 대단히 우수한 수준이고

 

일반 여자 성인에서는

 20대 미만(41.0 이상),

20대(45.1 이상),

30대(39.0 이상),

40대(38.0 이상),

50대 이상(33.3 이상) 이면 대단하 우수한 수준인 것으로 평가되고 있다