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VO2 Max


It is fairly well-known that with regular exercise your body can improve its function. We most often think of these improvements in the areas of muscular strength, heart rate and cardiac function, or body weight and composition. There is another function that improves with aerobic exercise that is noticeable but not often explained or measured.

Maximal oxygen consumption (VO2 max) is the amount of oxygen your body can use, per kilogram of body weight, per minute. It is a little like measuring your miles per gallon while taking into account how big your car is. Oxygen consumption is dependent, not only on your lung volume (how much air your lungs hold), but also how well your body moves that oxygen into your blood and delivers it to the right areas for efficient use. If your VO2 max is high, you will likely be able to do more strenuous activity for a longer period of time. Conversely, if it is low, you will quickly become winded with only minimal activity like going up a flight of stairs. Men typically have higher VO2 max measurements due to the increased size of their thoracic cavity where the lungs live.

The good news in all of this is that the body’s ability to use oxygen is highly trainable. There are still some genetic factors that can keep you from turning yourself into the next Lance Armstrong, but improvements can be made nonetheless. The key to making improvements is making sure your exercise routine is aerobic in nature. This means doing things that get your heart rate up for a prolonged time, like rigorous biking, running or long-distance swimming. Working out on machines like stair climbers and elliptical trainers can to the trick as well.

Thankfully, VO2 max is one function that is easy to measure and can help you make sure that you are working hard enough to get the needed benefits from your workouts. We have two calculators for you to use to determine the key factors. The first is to determine your estimated maximum heart rate on the heart rate calculator. This will calculate some percentages, allowing you to monitor your heart rate. Monitoring your heart rate will ensure the most appropriate exercise intensity is being maintained. The other calculator will help you determine your current value of maximal oxygen consumption. The procedure for testing your VO2 max is relatively simple. All you need is a stopwatch and the ability to walk 1 mile. Timing yourself, walk a mile as fast as you can. When you are finished you can record your time and your ending heart rate in the calculator. We do the rest to inform you of your current VO2 max. Some general principles to help you with your exercise planning are included below.

  1. Do a general warm-up for at least 5 minutes to get your heart rate and body temperature slightly prepared for impending demands of exercise.
  2. Shoot for working out for 60 minutes at a heart rate intensity of 70 percent of your max heart rate as calculated in the heart rate calculator. Too low of a heart rate intensity percentage will not give you the desired results.
  3. Make sure you workout at least 3 times per week. Less than that does not give your body the message that improvements are needed. Working out fewer than 2 times per week is actually a physiological stress to the body.
  4. Do a gradual cool down after your workout for 5-10 minutes to slowly lower your heart rate. This prevents blood that has been racing through your system from coming to a sudden halt, which could cause pooling in the veins.
  5. Retest your VO2 max again about every 3 months to track your improvements. Also, recalculate your estimated maximum heart rate. Regular testing will ensure that your workout intensity is sufficient for continual improvements.

Keep in mind that the VO2 max improvements made will not be visible. You may feel some of the improvements when you go up a flight of stairs, but the changes that are made are on the inside. Some changes are even at the cellular level. Your body will be impacted several ways with a consistent and well-structured aerobic program that is performed at the minimum of 70 percent of your maximum heart rate. These changes include:

  • Increased heart muscle size 
  • Improved stroke volume (the amount of blood the heart pumps in each beat)
  • Improved cardiac output
  • Lowered resting heart rate
  • Increased amount of hemoglobin in your red blood cells. Hemoglobin carries oxygen to the needed areas.
  • Improved ability for muscles to get oxygen from the blood (oxygen extraction) during your workouts
  • Improved blood pressure
  • Improved respiratory efficiency

All of these benefits will make your heart, lungs and blood vessels healthier and can benefit your life’s quality and quantity.