In a sub-maximal test workload is usually increased to a pre-determined heart rate or workload short of a maximal effort, or to a point that determines the lactate or anaerobic threshold next chapter. Formulas have been published to predict VO2max from a sub-maximal test, but there are considerable doubts about the accuracy of such predictions. A poor analogy might be to claim that you could predict the maximum speed of a car by accelerating to 55 miles per hour.
VO2max Maximal oxygen uptake was first described by Hill and Lupton in as "the oxygen intake during an exercise intensity at which actual oxygen intake reaches a maximum beyond which no increase in effort can raise it". To be sure, you can perform this supra-maximal effort for a very limited time, typically less than a minute. VO2max can be considered THE universal measure of aerobic fitness. It allows you to compare couch potatoes with runners, rowers with tennis players, swimmers with spinners, and so many more.
It does not tell you about their skill, just their relative ability to perform work. Let's look at two runners, equal in weight. Yet runner 1 beats runner 2.
This may be because runner 1 has better skills, running efficiency, Nike shoes, or better steroids. To this day, endurance sports like the biathlon, cross country skiing and the Nordic combined continue as bastions of the quadrennial event and, in fact, the six most decorated Winter Olympians of all time are all aerobic athletes who participated in these grueling endurance races.
But, considering how the Winter Olympics are generally held at higher elevations where oxygen pressures are lower than at lower elevations, it does raise questions over how these environments impact VO 2 and subsequently their aerobic training and performance - and whether these high-elevation athletes are any different from their summer counterparts who generally live and train at lower-elevations?
To understand these questions and more, we need to first dig a little deeper into the science and value of measuring oxygen consumption or VO 2.
This article will examine some physiology, application and the value of measuring VO 2 - given how this parameter is often considered synonymous with athletic performance. In its simplest form, VO 2 is the difference between oxygen inspired and oxygen expired in a unit of time e. As the word denotes, absolute VO 2 reflects the total absolute amount of oxygen consumed by a body, regardless of size, age or gender whereas relative VO 2 indicates that score corrected to some reference, which happens to be a unit of mass or one kilogram 1 kg.
The units of measurement are all metric:. Both absolute and relative VO 2 provide valuable information. Considering the role of oxygen in metabolism i. You can actually use VO2 to get a somewhat accurate picture of weight loss through metabolic equivalents. While not exact, scientists use an average of five 5 calories for every liter of oxygen consumed. Therefore, if Mary was running on a treadmill and consuming 2. Unfortunately, absolute VO 2 scores cannot be used to compare individuals against each other or against norms i.
Consequently, absolute VO 2 scores are converted to relative scores for purposes of comparison. For example, is Peter who weighs lbs. VO 2 max has long been considered a predictor of maximal exercise performance i.
Yet, it is not an effective measurement. A peak VO 2 or VO 2 max is a one-time best shot - an incrementally staged lab test - and does not represent a sustainable intensity, which is what all endurance sports require. If we look at the VO 2 -work slope of Figure 1. But additional intensities of work can be performed B-C. This plateau is believed to either represent a maximal capacity for mitochondrial oxidative capacity or an inability to further supply oxygen to the mitochondria through the blood 4.
Follow on below for a more in-depth explanation. And if you haven't yet pursued a NASM Performance Enhancement Specialization , there's plenty more great information within the course! These markers represent the highest intensity that one can sustain over time and are often referred to as lactate threshold LT , which is incorrect 1. Instead, lactate threshold represents the intensity of exercise at which the amount of blood lactate begins to rise disproportionally above normal resting values and it generally occurs early at moderate-to-vigorous intensities of exercise 3.
VO 2 is influenced by a myriad of other intra- and interpersonal factors that include 5 :. While VO 2 max holds limited value as an estimator of performance, it does hold great value as a predictor of overall health and in determining work capacity standards for various occupations. Individuals who are physically active generally have higher VO 2 max scores and present with lower risks for morbidity and mortality.
Likewise, as VO 2 reflects work capacity, many physically-demanding occupations e. Increases in elevation generally reduce ambient temperatures, both of which can negatively impact athletic performance. A common misconception is that at altitude the air holds less oxygen, making breathing harder, which, in turn reduces exercise capacity.
However, it is not the concentration of oxygen that presents the problem but the decreased pressure of ambient air pushing oxygen into the lungs and blood that is the issue.
At higher elevations, the total pressure of atmospheric air drops, therefore the partial pressure of oxygen also drops.
For example, at sea level, atmospheric air exerts a total pressure of mm Hg and with oxygen comprising At 14, feet 4, meters however, atmospheric air only exerts a total pressure of mm Hg and with oxygen comprising If you're really interested, your best bet is to search "VO2 max testing near me" on Google.
To measure VO2 max, you wear a mask and heart rate monitor hooked up to a treadmill or stationary bike. The mask is connected to a machine that collects and measures the volume of oxygen you inhale, and the amount of air you exhale. Once you reach that plateau, your body moves from aerobic metabolism to anaerobic metabolism — that is, your body stops using oxygen to fuel the breakdown of carbohydrates, amino acids, and fats because there isn't enough oxygen there.
Shortly after you reach that switch, your potential workload plateaus and muscle fatigue sets in. You have to return to an aerobic state of movement to keep going. Like heart rate, there's no one "good" VO2 max.
Your VO2 max will differ from someone else's based on age, gender, fitness level and outside factors like altitude. For example:. If you ever do get around to visiting a sports performance lab and getting your VO2 max tested, it'd be worth it to act on that number.
Increasing your body's capacity to utilize oxygen is one surefire way to get you closer to your endurance-related goals — a higher VO2 max essentially extends your breaking point. You might not be too surprised to learn that high-intensity interval training is one of the best ways to improve your VO2 max. It works because you train your body to work at incredibly high levels for a period of time just long enough to push or surpass your anaerobic threshold before returning to a steadier, aerobic state.
In a theoretical sense, any exercise that pushes your limits can increase your VO2 max. Think of it like building muscle: Muscles won't grow unless they're exposed to workloads that challenge them.
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