What would happen if you asked your doctor to precisely prescribe you a fitness regimen for optimal health? Might they have an answer for you? Of course they’d have some sort of answer, but it would most likely be somewhat general…something like, ‘well yes, you should be doing some cardio throughout the week for your overall health, whether it’s biking, running, etc.’
Yes, but doc…what exactly should I do? Like, how many days per week, for how many minutes or for what distance? And when we say ‘cardio’ do I just hop on the elliptical at PF and go? Does it matter how hard I go? Should I do a slow jog…or an all out sprint?
Chances are, your doctor won’t be able to give you this. It’s not their fault. Our medical field is more set up for treatment of issues rather than slow and long-term prevention, with lifestyle interventions. However, this type of practice is central to our health, for right now and more importantly for our healthspan and longevity purposes.
Before we get to the details of ‘cardio’, we should mention that there are certainly other buckets to fill in order to optimize health. This isn’t the only work we have to do. We should also be taking careful consideration around nutrition/supplementation, strength training, sleep, and emotional/mental health as well. I’ll be writing about these (and have already written some about them) in future posts.
Zone 2
The first method in building up our cardiorespiratory health is to build the width and base of the pyramid. We do that by spending basically as much time as we can in zone 2. To access this cardiovascular Zone, we need to maintain a heart rate that allows us to hold a conversation while exercising, but one where our breath rate is certainly elevated. You can use running, biking (stationary bike is great as you can control the rate more effectively than you can with elevation changes, traffic, etc. on the road), or rowing as a few examples. If we are really out of shape or have been sedentary for a while, even a brisk walk will bring us into this zone. I can usually maintain nasal-only breathing in my zone 2 training. If my heart rate goes up too high, I have to start mouth-breathing…and then I know I’m out of zone 2. Here is a small chart to help illustrate the zones:
Zone 1 (recovery, very easy) 55-65% of max HR
Zone 2 (aerobic, base) 65-75% of max HR
Zone 3 (Tempo) 80-85% of max HR
Zone 4 (lactate threshold) 85-88% of max HR
Zone 5 (anerobic) 90-100% of max HR
Zone 2 training should take up about 80% of the time we spend on cardiorespiratory work. This broadens and widens out the base of our pyramid. All sorts of good things are happening in the body when we sustain a heart rate in this zone. The main benefit is the overall improvement of our metabolic health…that is to say how effectively we use fuel in the body. How do we use glucose and fat to fuel us? Aerobic training improves the health of our mitochondria. These little friends are the workhorses inside our cells that create energy (in the form of ATP) for us to then go function throughout our lives.
According to Peter Attia, MD, ‘Healthy mitochondria are also important to maintaining the health of our brain, and to controlling potential bad actors like oxidative stress and inflammation.” Therefore, we can also be stoked that zone 2 training helps us with cognition and memory, producing brain-derived neurotrophic factor (BDNF), and helping us prevent neurodegenerative disorders like dementia and Alzheimer’s. We oughta treat these little mitochondrial friends really well, as the payback is immense for us, and moreso as time goes on.
If we’re just starting out, we should strive to be in zone 2 for at least 2 sessions per week of 30 minutes each. There is a huge benefit from going from being totally sedentary to getting your body into this type of movement each week.
If we’re already pretty active, athletic, or have already reached that level, we should strive for 3 hours per week…either 3 separate 1 hour sessions, or 4 separate 45 minute sessions. I know…that’s a lot. It’s a slog. BUT, what’s great about zone 2 is that you can make phone calls during these sessions. You can catch up on your podcasts and audiobooks. Hell, you can even put a treadmill or stationary bike in front of the TV and do it there. If 3 hours per week of Zone 2 sounds like a lot, we should ask ourselves how many hours per week of television we are watching…and whether or not that number sounds like a lot. Hmmm.
VO2Max
The other phase of training we benefit from practicing is a much more challenging activity. We will be breathing hard. Our heart rate will be elevated (up through zone 4 into zone 5), and we’ll need to spend time recovering. This is VO2Max training.
VO2Max is the Rate (V) at which your body can consume oxygen (O2) during exercise. Oxygen comes into the lungs, runs into the bloodstream where it flows through capillaries in the muscle fibers to help create movement. Well the higher the rate you can take in oxygen and process it through your body with movement…the higher VO2Max you have…and more importantly, the healthier you are as an individual.
A high rating in VO2Max generally provides us with a high capability to carry out anything physical. This number of course drops with age. And you can consider how hard it would be for a 90 year old to carry a bag up 2 flights of stairs. They cannot take in oxygen and process it into functional movement at the rate and efficiency as a 20 year old can. They of course may have other variables contributing to this, but their oxygen uptake and utilization is one of the main reasons. This is why it’s so important for us now to maintain, and continue maintaining a high VO2Max number.
Now, the zone 2 training will certainly help our VO2 max number…a little. But it’s more effective to think of that pyramid again, and the fact that zone 2 will slowly build that nice wide base. We can think of it more as giving us the opportunity, or platform to then use VO2Max training, to really raise up the peak of the pyramid.
‘Ok, so doc, how should I train this system?’ one might ask, sitting on the loud paper covering the exam table…feet dangling in the cool air. Well, the good news is that it involves waaay less time, and needs to happen less often than we should be training our zone 2.
For VO2Max training, we can use this easy to remember practice of a 4 by 4. We should use 4 intervals of 4 minutes each, going as hard as we can…with 3-4 minutes in between each interval in order to get our heart rate back down. I like using running for this…or an airbike…so that I can get my entire body involved and somewhat max everything out. Biking on the road or all out rowing is challenging for me to reach that peak exertion.
Now remember, we can’t necessarily ‘sprint’ for 4 minutes straight. Maybe we could absolutely sprint for a minute, but then the final 3 minutes of the first interval would be slow and sluggish. Knowing that we have to push against our maximum capacity for 4 minutes straight, and also knowing that we have to do this 4 times, we will somewhat subconsciously ‘pace’ ourselves through this. BUT, don’t pace too much. You NEED to be pushing up against that maximum output for all 4 intervals of 4 minutes in this exercise. You need to tell the body to use more oxygen…and use it better…more effectively! Tell those little mitochondria to fire up their little engines and get ready for a few drag races.
This is where the 3-4 minute recovery between rounds is very important. If you don’t recover enough, you won’t be able to push out your max in that next interval, and you won’t cause the adaptation to your system that you’re looking for. Use a very slow jog or ‘zone 1’ recovery for these in-between segments. Then go like hell when it’s time to fire it back up!
Oh, you only need to do this once per week to cause sufficient adaptation. If we are elite athletes, we could perhaps do this twice per week. But just once will do wonders.
Another thing to mention is that if you haven’t gone all out for a long time, you definitely risk injury doing so all of a sudden. Build your tissues up to this. Use a good 15 minute warm up, and some dynamic movement beforehand so that you’re not expressing maximum output on a cold, fragile body. This is where strength training, and building from the ground up…building up connective tissues in the joints, etc. play a huge role. Separate topic, but inseparable! After you’re done with your 4×4 VO2Max session, use a brisk walk or jog for 15 minutes or so as a cool down before totally stopping and hitting the shower. I like to stretch after my max outputs as well because the muscles have been tightened up and used…well, to their max. Therefore, stretching them out back into place leaves me feeling flexy, and not all rigid and tight walking around for the rest of the day.
Measuring our VO2Max
We could simply keep training these zone 2 and max output interval sessions, knowing that we’d improve our actual VO2Max number. But where is the fun in that? I love to gamify whatever I’m doing if possible. I love to find ways to compete with others, or compete with myself if I can. Therefore, knowing my number is important to me.
If we have a fancy smartwatch, like an Apple or a Garmin, we may be able to obtain our VO2Max number there. How convenient!
Well I don’t have those. And I actually like an old fashioned method of what is called the Cooper test. This consists of running as far as you can for 12 minutes straight. Take your exact mileage, plug it into an equation, and find your number that way. Here’s the equation:
(35.97 x (your distance in miles in the 12 minutes) – 11.29 = your VO2Max
The distance I ran last week was 1.66 miles. Therefore:
(35.97 x 1.66) = 59.71
59.71 – 11.29 = 48.42
You can also find online calculators for this. Here is an image of one that I used to check my number in another method…it came out exactly the same:
So now that I know my VO2Max number is 48.42, I’ll consistently use my zone 2 training (aim for 3 hours per week) in addition to my Max training (one 4×4 session per week) to try to increase that number.
I’d love to hear what your number is, and how much you’re using this type of training to improve it. Please write to me!
– James
jimmythorpe.com 