Whether your doing an aerobic class at the gym, cycling, playing tennis, skiing, or running, your body depends on endurance achieved by oxygen (O2) consumption and optimal utilization (by the muscles) of oxygen.
We know that the heart is a muscle and it must be exercised to stay healthy and strong. We also know that the stronger the heart is, the more blood is pumped out and the more O2, via our blood, gets delivered to our muscles. Once O2 is diffused into the muscle cells, its job is to reach the mitochondria (the “power house of the cell”) where it is used in the production of adenosine triphosphate (ATP). ATP is the energy muscles need to do work. This sounds pretty important, huh? I bet you want to know how is O2 consumption measured during exercise?
Oxygen consumption (Vo2) is the volume of O2 inhaled minus the volume of O2 exhaled. It is usually measured in a lab with some sophisticated testing apparatus by medical students, scientists, or elite athletes and coaches to determine these measurements. VO2 Max is the maximum amount of oxygen (O2) that an individual can utilize during intense or maximal workouts.
Oxygen rises linearly with exercise intensity until the O2 consumption plateaus, even if intensity continues to increase. The point at which oxygen plateaus is the VO2 Max. VO2 Max is a great indication of your cardiovascular fitness and has synonymously been used with the terms aerobic or cardio fitness. The take home message is this: if you exercise and begin to increase your intensity, you will increase your cardiovascular fitness or VO2 Max. If your muscles get stronger and more efficient during their workout, they will be better able to utilize O2. The more the muscles get a work out, the more capillaries are made in the muscle tissue. More transport capacity (capillaries) for blood equals more O2. This sounds great!
“I don’t have access to this expensive testing apparatus so how will I know if I am increasing my VO2 Max?”
There’s really a few ways to do this, but I will out line two simple ways:
1. Monitor your exertion. Go to your local high school track. Use either a fast paced walk, a jog, or full-out run, count how many laps you can do before you physically cannot go on any further. That number is your base. From now on, your goal must exceed that number of laps. To mechanically fatigue at any number beyond your base would indicate an increase your estimated VO2 Max.
2. If you want to measure your estimated VO2 Max using a calculation rather than your perceived exertion and number of additional laps ran, use the Balk Test: You’ll need a stop watch and a 400m track.
Note: 1609.344 meters= 1 mile
• Pick a day that’s not windy, set your watch to beep at the end of 15 minutes, and take the track for 15 minutes.
• Calculate the total number of meters walked, jogged, or ran.
• Use this formula (you may want to use a calculator)
(((Total distance covered /15) – 133) x 0.172) + 33.3
Example Case: 40 y/o non-athletic female:
1600m / 15 = 106.6667
106.6667-133 = -26.33333
-26.33333 x 0.172= -4.529333
-4.529333 + 33.3 = 28.77067 (note she falls within normal limits for her age)
Age Males Females
30-39 39-48 30-38
40-49 36-44 26-35
50-59 34-41 24-33
NOTE: Environmental factors have a lot to do with our cardiovascular system. Heat and humidity can put us at risk for heat injuries, so please see your doctor, drink water every 10-15 minutes, and wear wicking materials when you exercise. If you’re in temperatures that are cold and blustery, be aware that some of you may do better in colder weather then in the heat. As it gets warmer, conduct your exercise indoors or start your workouts before sunrise or at sunset.
There are other variables such as heart rate (HR) and the amount or percentage of aerobic power to use per fit or unfit individuals. However, this is as far as I will go for right now. If you have any questions, please send me a comment and I will write you back.
Go estimate your VO2 Max and join me tomorrow as I discuss how to achieve fat loss and how it ties into VO2 Max!
Note: Always check with your doctor before starting any fitness regimen. A thorough check up can’t hurt and should be done every year. Many of the routines and diet plans that I create for myself may not be suited for you. Ask me questions so I can help you if you have any limitations.