Occasionally, drawing on my deep memories of Captain Kangaroo, I find myself silently repeating “I think I can, I think I can.” Have you been there? Maybe at times when you were attempting something new, or encouraging yourself toward some improvement? You may remember that ‘mantra’ from the children’s story The Little Engine that Could, admittedly one of my favorites. [Captain Kangaroo read this story of the choo-choo often.] Aside from will-power, I am not certain what type of energy powered that train. There had to be some. The same goes for us. Will-power is terrific, but an energy source is vital.
You might recall that in my March article Can ALL Seniors HIIT Improved Levels of Glucose Safely, I stated that I wasn’t going to defend my fitness improvement by self-determined numbers. Not that I couldn’t, but I didn’t want to rely on it. [I wasn’t referring to glucose levels but to fitness capacity.] One of the best definitions of fitness is our own personal energy – not just the ‘I-think-I-can’ power, but having the oomph to back that up in our everyday lives.
Where does this Energy come from?
One surprising part of this answer is that the major creator of energy in our bodies does NOT share our DNA. Not only that, this little invader is found in every cell of our bodies – each cell having some, even up to many thousand. You know their name, whether you remember what they do or not. These ‘aliens’ are Mitochondria, often described as the power plants of our body. These bacteria-like powerhouses can transform materials of oxygen and glucose into little bundles of ATP (technically known as adenosine triphosphate) – used to power your body. Being such spectacular creatures, should we covet even more of them? Yes. And the way to achieve that is through aerobic activity. That’s all of us, not just those 20 years old, or 40, or 60, but all of us.
To measure that aerobic capacity we look at the oxygen that is available to us. “VO2 max” is short-hand meaning your maximum volume capacity to move and use oxygen (especially during exercise or activity). It is also the way our little alien-friends (Mitochondria) are increased.
First Tip: Don’t let all the Numbers Scare You
VO2 max is a spot-on way to evaluate fitness when determined in a lab or sports center, or when your doc uses a spirometer to measure your lung capacity. However, I am not convinced that “at-home” formulas work that well without added precaution. Nevertheless, let me briefly share the 2 formulas needed for determining your own VO2 numbers. And how, with a little more effort than what I personally hoped to expend, you can achieve reliable measurements even on your own.
Improving your VO2 max can improve your fitness and thus total health. Most likely, you have heard that before; but probably let it ‘go in one ear’ and …… You may believe it is relevant only to athletes. That belief is simply not true. Your own fitness (no matter your current level or age) can be improved. And if you want to know for sure it IS improving, you require these numbers for verification. Some folks are happy just to know they ‘feel better.’ That’s terrific. Others want the science to back them up. Or maybe just the bragging rights.
Determining Your Maximum Heart Rate – when you aren’t an athlete
We must start this evaluation of fitness by discovering our “maximum heart rate” number first. There are home tests, but not all methods of evaluating max heart rate are accurate (including what I am about to introduce below as a ‘default’). Yet, I will begin with another self-test approach (better than my ‘default’). Pick an activity, such as running or cycling, and do it against resistance (like uphill) for 3 minutes, rest for a few more minutes, and then start another burst of 3 minutes. [As I admitted, this is more effort than I had hoped to exert.] Somewhere during that second burst you will reach your max heart rate (best if recorded by a monitor versus your own pulse counting).
Done correctly, this self-test will produce outcomes fairly similar to a lab. [A friend helping in the one-time event can improve your recording – and keep you honest.] There are numerous blogs and websites that can guide you through this process and tell you more than you ever wanted to know. Unless you consider the less-accurate (default) formula I am about to share adequate, this 3-minute approach with a heart rate monitor is useful for more exact determination. And the heart monitor can be useful later to track further activity.
NOTE: I doubt there is a 4G smart phone on the market that doesn’t already have a heart monitor installed. My new smartphone (new by necessity – not choice) has a very easy-to-use heart monitor; you can use it for resting, pre-exercise, exercise, general. And 3G phones can usually download such apps. So you may either already have one or at least not have to spend extra money if you want to procure such a device.
For those either ‘out-of-shape’, not wishing to enlist your doctor for help or just unwilling to tackle the harder (3 minute segments) method above, there is an alternative. The safest home method to estimate your maximum heart rate (again, not the most accurate), is to use this formula:
Max Heart Rate = 205.8 – (0.685 x age)
[Reminder for we math-challenged folks:
you preform the calculations within the parenthesis first.]
The reason for its inaccuracy level is that it is determining your maximum heart rate based only on one personalized number – your age. I am certain I know people ‘my own age’ in much better shape; conversely I know some much less fit. Still, whatever way you arrive at it, you have to have this value (max heart rate) before the next step in the calculation can be completed.
Now, Determine Your Own VO2 Max
Granted, the most reliable VO2 results are obtained professionally, as mentioned. But without a machine such as the spirometer to figure your VO2 max, you need the previous maximum heart rate number, as well as your Resting Heart Rate to continue. [if you want a refresher in the best way to find that resting number, review my January post Heart Protection in 10 seconds or resort to your cell phone app.] With these numbers you can approximate what your own VO2 max is by computing this formula:
VO2 Max = 15.3 x Heart Rate Max / Heart Rate resting
After completing this calculation, you compare it to a chart. Below is a summarized outline, although be aware there are more detailed and informative charts available, AND they don’t all agree. I summarized data from Fast Exercise by Michael Mosely and Peta Bee (Atpria Paperback 2014). At the Fast Exercise site you can find calculators for both men and women.
|Age (Years)||Very Poor||Average||Excellent|
|Women||40-44||< 22||30-33||> 41|
|Men||40-44||< 26||36-41||> 51|
|Women||45-49||< 21||28-31||> 38|
|Men||45-49||< 25||35-39||> 48|
|Women||50-54||< 19||26-29||> 36|
|Men||50-54||< 24||33-36||> 46|
|Women||55-59||< 18||24-27||> 33|
|Men||55 -59||< 22||31-34||> 43|
|Women||60-65 +||< 16||22-24||> 30|
|Men||60-65 +||< 21||29-32||> 40|
So what? What does this tell Me & How does it Improve Anything?
Using high-intensity interval training or HIIT can yield functional improvement with impressive results. This is done by performing as few as 3 bursts of 20 seconds each, 2-3 times/week. Following that routine, many people increase VO2 max (that prime key to fitness) by 12-15% NO MATTER OUR AGE.
Studies by Vollaard and others explain that by pushing our bodies to a high level of effort, we trigger what is known as the “afterburn” effect. [Again, not just for athletes.] Afterburn means that our body continues to ‘work’ after our workout is done by consuming O2 (oxygen) for hours – most references say 48 hours. I love getting something for free.
Afterburn has a more technical term called EPOC which stands for Excess Post-exercise Oxygen Consumption. Interestingly, because of this afterburn (EPOC) we also burn 5 more calories for every liter of oxygen that the body continues consuming. Good deal.
My Home In-Accuracy and Personal Example?
As I attempted to track changes using HIIT, why did I discount the ‘default’ max heart rate method? Because on a personal level I am convinced the result of this strictly “by-the numbers” approach is not very accurate. Using the default formula, the only number I was certain about (aside from age) was my resting heart rate, which I take frequently. My number is quite reliably between 56-60.
Luckily for me the resting heart rate is a powerful predictor for future health. I have that going for me. But without professional evaluation of my VO2 max, or at least more arduous maximum heart rate testing (as in the strenuous 3 minute x2 self-test above), it seems to me my results must be wrong. When I plug my numbers into the VO2 max formula and then look at the chart for my age, the result is not only “excellent” but more than 10 points better. Am I that fit? Absolutely not. I would like to be, but am not.
I am not unfit either. Yet, I live in an area about as hilly as San Francisco and find myself walking uphill a lot. I am not so fit that I bounce up the street. No, even at a slow pace, I am breathing heavily at the top. You might be tempted to make excuses for me, instead of just saying I need more exercise. That would be nice of you. Still, my point is that I cannot be 10 points better than the excellent score; I realize this. That also means the formula can be pretty far off. Or the chart is excessively lenient.
I point this out to demonstrate that the ‘easy’ maximum heart rate formula alone can be misleading. Conversely, if someone is obviously heathy enough, or their physician claims so, and is less lazy than I am, then the self-test of two 3-minute resistant segments does provide numbers close to a lab or clinic.
When you know that specific number (you maximum heart rate) then the formula for the VO2 max is also fairly accurate, even without the fancy testing.
Not for Me?
Finally, some readers will be of the age or attitude, in which they proclaim;
“it is what it is – I’m not putting any effort into increasing my fitness.”
On one hand, I accept this position and fully believe life is more than just quantity of days. On the other hand, for those who are still fighting for more days, or valuable strength and health to accomplish more within those days, then fitness (in the terms of oxygen intake) is vitally important. Even if it simply makes your ADLs (Activities of Daily Living) easier, it may provide that one key to longer independence we all want to keep.
And for those who still want to augment their fitness despite the looks from others who think you are ‘past that age,’ improving VO2 max is essential.
It’s all about that little engine that could. Will-power, yes, but ‘go-power’ too.
References – below see several of the many sources on Afterburn (EPOC) for those who want more reading:
American Council on Exercise. Afterburn (EPOC) https://www.acefitness.org/blog/5008/7-things-to-know-about-excess-post-exercise-oxygen
Afterburn earlier research (U. of New Mexico) https://www.unm.edu/~lkravitz/Article%20folder/epocarticle.html
Bersheim, E. and Bahr, R. (2003). Effect of exercise intensity, duration and mode on post-exercise oxygen consumption. [Originally from Sports Medicine, 33, 14, 1037-1060]
LaForgia, J., Withers, R. and Gore, C. (2006). Effects of exercise intensity and duration on the excess post-exercise oxygen consumption. Journal of Sport Sciences, 24, 12, 1247-1264.
Spinning. Understanding the science of EPOC- good lay person’s reference to EPOC and charts for longer, less intensive workouts.
Picture credit: Train; tevyaw 673642_1280 courtesy of Pixabay