VO2 Max Testing

VO2 Max Testing

What is a VO2 Max Test?

A VO2 Max Test is a measurement that reflects a person’s ability to perform sustained exercise. It is generally considered the best indicator of cardiovascular fitness and aerobic endurance.

VO2 max serves as one of the best measurements of your cardiac health. In fact, the American Heart Association recommends adding it to the list of vital signs, such as blood pressure, that doctors test during patient encounters. Doctors express VO2 max as the amount of oxygen in milliliters your body consumes in 60 seconds for each kilogram you weigh (mL/kg/min).

Each breath you take pulls oxygen into the body, where it enters the bloodstream. Then, your heart pumps this oxygen-rich blood throughout the body, where it enters the muscles and triggers chemical reactions to create energy. Specifically, the oxygenated blood breaks down carbs, fats, and proteins for fuel. When we’re working out, we need more fuel than usual, which is why we begin breathing deeper, faster, and harder during a tough workout. When we exercise, our heart and lungs get stronger, making it easier for the body to distribute blood and oxygen. when you train to raise your VO2 max, you’ll be impressed by your newfound endurance.

Frequently Asked Question about VO2 Max Test

What is Anaerobic Threshold?

The anaerobic threshold (AT) is defined as the level of exercise intensity at which lactic acid builds up in the body faster than it can be cleared away. Lactic acid build up generally leads to muscle fatigue and soreness. Vigorous effort can be sustained for an extended duration at exercise intensity levels below the anaerobic threshold. AT can be detected by 2 different means: Ventilatory Threshold, or Respiratory Exchange Ratio threshold.

Respiratory Exchange Ratio (RER) is the ratio of expired carbon dioxide to oxygen uptake at the level of the lung. When Carbon dioxide production exceeds oxygen uptake, the RER crosses 1.00. This is anaerobic threshold.

Ventilatory Threshold (VT) is the point during progressive exercise in which ventilation increases disproportionately to oxygen uptake. Ventilation increases to rid the body of the excess Carbon dioxide from lactic acid build up. AT is detected by pinpointing the take off (rising) point in the Ve/VO2 ratio. (Meyers, 1996)

What is the difference between Anaerobic Threshold and Lactate Threshold?

Lactate Threshold is a reference to the accumulation of Lactate in the blood. There are some inconsistencies in the terminology, though. Some use the term to denote the initial rise in lactic acid production. More often, Lactate Threshold is used to describe the maximum steady state effort that can be maintained without lactate continually increasing. This abrupt increase in blood lactate levels is also referred to as the lactate turn point (LT), lactate inflection point (LIP), or onset of blood lactate accumulation (OBLA). (Roberts & Robergs 1997)

The Anaerobic Threshold is defined as the level of exercise intensity at which lactic acid builds up in the body faster than it can be cleared away. Because this is measured by Ventilatory responses (Ve/VO2 or VO2/VCO2), it is often more accurately termed Ventilatory Threshold (VT). (Meyers, 1996)

What is the difference between RER and RQ?

Respiratory Exchange Ratio (RER) is the ratio of expired carbon dioxide to oxygen uptake at the level of the lung.

Respiratory Quotient (RQ) is the ratio of expired carbon dioxide to oxygen uptake at the level of tissue or cells. Sometimes this term is used interchangeably with RER, but that is incorrect. A VO2 Max test measures RER. (Meyers, 1996)

Do you need to measure CO2 to detect Anaerobic Threshold?

The key to determining Anaerobic Threshold (AT) during a VO2 Max test is to detect the point when the body is forced to expel the surplus CO2 produced as a result of excess lactate. This can be determined one of 2 ways:

Measuring VCO2/VO2 (volume CO2/volume O2) and detecting the point when that ratio (RER) equals 1.00. This is the Respiratory Exchange Ratio method.
Measuring Ve/VO2 (Minute Ventilation/volume O2) and detecting the respiratory compensation point. This is the ventilatory equivalent method.
Multiple studies (1,2) have shown that both methods are valid and reliable for determining AT among healthy subjects. KORR offers products that utilize both methods of AT detect to best meet customer needs. A comparison of methodologies in detection of the anaerobic threshold. Dickson K, Barvik S., Aarsland T, Snapinn S, KarlssonJ. Circulation 1990 Jan;81(1 Suppl):II38-46. A new method for detecting anaerobic threshold by gas exchange. William L. Beaver, Karlman Wasserman, and Brian J. Whipp Journal of Applied Physiology 60:2020-2027, 1986

How does VO2 Max differ between men and women?

Women typically tend to have a lower VO2 Max than men.

Does VO2 Max change with age?

For men and women, VO2 Max will decrease by 10% per decade regardless of age and exercise activity.

Is VO2 Max affected by a person’s size?

VO2 Max is unique to each person and directly proportional to their height, weight, and body surface area. VO2 Max correlates 0.63 with body mass, 0.85 with fat-free body mass, and 0.91 with active muscle tissue.

Does where I live affect my VO2 Max?

VO2 Max is reduced for residents of temperate or tropical areas (compared to those living in circumpolar regions). Also, VO2 Max is reduced by approximately 26% at an altitude of 4,000 meters. This reduction increases as altitude increases.

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