The 2 health metrics I really care about
Why I'm focusing on VO2 max and Body Fat %
👋Hello, my friend. I hope the weekend is treating you well. I’m coming to you today with an article I’ve been meaning to write for a while. It’s an overview of my latest efforts to improve my own health and (hopefully) longevity… and how I’m focusing on two metrics to do exactly that. As you might know by now, I love to nerd out on all of this type of stuff and maybe-just-maybe all of this nerding out might benefit you in some small way.
So, let’s get into it!
Oh, but before we do……. a quick shameless plug for my son’s baseball fundraiser. He and his squad have been playing together for about 5+ years. The thousands of hours of games and practices are about to culminate in the trip of a lifetime to play at the Hall of Fame in Cooperstown, NY this June. It’ll be a capstone on his youth baseball career - and it should be awesome. It’s basically a dream come true for 12 year-olds.
Think: Incredible stadium. Short home-run fences. And a week of staying in the “barracks” with your best buds while you compete with teams from all over the country. The catch? It’s kinda pricey… hence the fundraiser to pay for everything along the way. If you’d like to support Charlie in his baseball dreams, please check out the link below. 🙏
The Two Health Metrics I Really Care About
1. VO2 Max - the best predictor of mortality
Last year, I became borderline obsessed with Zone 2 training, which is basically long, slow cardio sessions meant to improve aerobic function. If you need more details, I wrote this primer on all things Zone 2.
The good news? With all of that focus, I was able to re-establish a running habit after 10+ years away from it. I saw some marginal improvements in my VO2 max. And, I even ran a 5k with my kids - which was fun.
The bad news? My cardio fitness did not improve nearly as much as I had hoped it would. How do I know? Because I recently went to a clinic where I got my VO2 max tested and… it wasn’t super impressive.
What is VO2 Max?
It’s a measure of how efficiently your body uses oxygen during exercise. In layman’s terms, it’s a pretty damn good measure of just how “in shape” you actually are. According to Dr. Peter Attia, who has produced as much great content on this subject as anyone…
“It is more strongly associated with reduced mortality risk than any other metric we know of..”
That’s right. The higher your VO2 max, the lower your chances of dying… of anything. It’s a better predictor of all-cause mortality than blood pressure, cholesterol, weight… you name it. In other words, it’s a really good measure to track if you’re trying to live a long, healthy life.
How is it measured?
It’s pretty simple, even if it’s not pleasurable. You go to a lab or a clinic or some type of facility that tests VO2 max. I went on Google and found one about 2 miles from my house. Some facilities measure you on a stationary bike, others on a treadmill. Either way, an airtight mask is placed over your mouth, and you run (or pedal) at an increasing rate until you no longer can keep your effort in a pre-specified range. For most people, the test lasts about 8 to 15 minutes. And it’s not that much fun.
But it’s worth it. Because you get all sorts of data from helpful heart rate measures to, of course, your VO2 max.
How to interpret your #’s
So what’s a “good” VO2 max? Well, it depends on your age and gender. Below is a table I stole from REI.com that lays it out nicely. As I mentioned, I don’t think my stats were very impressive. I had a VO2 max of 34.5 ml/kg/min - right around where that red X is below. So kind of average-ish, maybe, for a 45-year-old man, but really not too impressive… at all. And, I’ll admit, I thought I was kind of in good shape so that was a little disappointing to see. Also, quick note for those who pay attention to the V02 max proxy measure called Cardio Fitness on their Apple Watch…. my watch had been giving me values of 37, 38, 39… for the last few months. So, those turned out to be slightly inflated vs. the clinically tested number. Your mileage may vary.
My plan to improve my VO2 Max
For the reasons mentioned above, I really want to improve my VO2 max. Somewhat arbitrarily, I’ve set a goal to attain a 45 VO2 max by year-end. That would put me in the top 25% of men my age. I’m not sure if that’s too aggressive or not aggressive enough but that’s where I’m starting. From everything I’ve read and listened to (some of those links are below), the most effective ways to improve VO2 max involve moving your body — both for long periods of time (aka Zone 2) and for short bursts of intense activity.
As I mentioned earlier, in 2023, I did a lot of Zone 2. I read and listened to a lot of material that said you should be doing 80% of your cardio in Zone 2 — so basically a slow, conversational pace for 45 minutes or more. I did this with slow runs and easy Peloton rides. The remaining 20% should be high intensity workouts. These can be things like hill sprints or anything that gets your heart rate up near its max rate. For me, Peloton 20-min HIIT or Tabata rides or 30-min Intervals & Arms rides seem to do the trick. I hook up my heart rate monitor and I get myself up to max heart rate, which for me is ~177 bpm. It’s kind of amazing actually how much work you can get in in 20-minutes when you’re going full throttle.
Now, in listening to a recent podcast with Dr. Rhonda Patrick, who I’ve come to really like, I’ve concluded that I was doing too high a ratio of Zone 2 last year and not enough high intensity. Dr. Patrick points out that, yes, the 80/20 ratio is correct if you are an elite athlete and you’re putting in say 20+ hours of cardio per week. But most of us are nowhere close to that. Last year, a typical week for me was more like 3 Zone 2’s x 45-mins each + 1 30-min HIIT ride (with strength training on the other days). That put me at roughly 120 mins or 2 hours of focused cardio per week with only one 30-min HIIT session.
Long-story short, I don’t think that was enough intensity. And as Dr. Patrick points out, if our volume is not “elite athlete” type volume, that 80/20 ratio is probably not the right one for us. We may want to consider something more like a 50/50 split.
So, my plan for this year, which is already underway, is to go to two Zone 2 sessions per week and 2 HIIT sessions per week (plus strength training ~3 days/week).
Finally, everything I’m reading and listening to, especially the work of Dr. Alan Couzens, is convincing me of the power of walking. As such, I’ve committed to walking 8000 steps per day every day this year. Now, 8000 steps is really not that many, but if I’m honest, I have lots of days when (even if I do a Peloton ride), I’m still driving to work, sitting all day, and then driving home and sitting more. And I can easily miss that 8000 number. I don’t think that’s great. So I’m aiming to accomplish the 8k/day x 365 with a combination of runs, lunchtime walks, and a new addition - an under desk treadmill, which, so far I’ve found to be “just okay”… I much prefer to walk outside but if the weather is terrible and I need those steps, it does the job.
Lastly, I’ve added the Steps App to my Apple Watch so that steps # is always front and center. And if you’re interested in the “201” version of getting your steps in, I recommend trying out rucking. You can freak your neighbors out by strapping a 20 or 30-lb pack on your back and strolling around like I recently did on the coldest day of the year in North Carolina. It’s fun… if you’re into that sort of thing. (Remember the “nerding out” reference above?).
So that’s how I’m thinking about VO2 max. Let’s move on to measure #2….
2. Body fat Percentage
Most of us realize that weighing a little less probably would be good for us. But of course, it’s a bit more involved than that.
Traditional Body Mass Index (BMI) numbers can be lacking in detail at best and completely misleading at worst. For me, I think I’ve more or less had a false sense of my own health and body composition based on the fact that my weight is pretty low (~175 lbs) for my height (6’1”). According to standard BMI measures, I’m golden! The picture of health!
Unfortunately, a closer look at my body composition tells a different story. Recently, I got a DEXA scan, which is essentially a low-radiation X-ray of your full body that gives you an excellent sense of everything from bone density to body fat percentage.
My results, unfortunately, were quite disappointing. My BMI of 22.9 was in the middle of the “Normal” range. Great, right? I wish. Turns out that my body fat % was 28.4%. If you look at the chart below (and by the way, optimal levels vary significantly by gender and age), 28.4% puts me in the obese range. Obese! Not even just Overweight. I only have three letters to describe my reaction to this news: W.T.F……. Seriously though, this was pretty surprising. I’ve always been on the lankier side, and yeah, maybe I’ve gotten a little bit soft around the mid-section in middle-age, but wow, obese?!? This is a serious wake-up call… especially for someone who prides himself on working out nearly every day and eating (what I think is) very healthy.
I’m not going to waste a lot of ink here telling you about the risks of having excess fat on your body. Look at pretty much every terrifying disease from diabetes to cancer to heart disease and the risk of getting any of them pretty much skyrockets when you’re carrying around too much fat.
Improving Body Fat Percentage
So… I’ve got my work cut out for me. This may be too aggressive, we’ll see, but what I want to do this year is get my body fat % to 17%. That would put me squarely in the middle of the Healthy Weight range. Now, it’s a little more complicated than just losing fat because my body weight is actually close to ideal — I think 170-175-ish is a pretty good weight for my height — it’s the composition that’s the problem. I have too much fat and not enough muscle.
So how am I going to do it? Well, let me tell you my plan. And by the way, I don’t claim to be an expert here - if I were, I probably would have already figured this out. If you have better ideas, let me know. Leave them in the comments so others can benefit, too.
Exercise - I’ve already told you what I’m doing for my VO2 max but basically the plan is this:
2 x 45-min Zone 2 runs or rides per week
2 x HIIT / Tabata / Interval rides per week (usually 20-30 mins each)
Walk 8k steps per day
Strength train 3x per week for 45-mins rotating between:
“A day” - bench, chest flys, overhead press, push-ups
“B day” - assisted pull-ups, deadlifts, goblet squats, single-arm rows
Diet - I’m broadly trying to follow the “slow carb diet” which Tim Ferriss explains in this 10-min clip. It’s basically focused on eating high-protein, low-carb, and not drinking calories. It also includes one day per week (I’ve chosen Saturdays so far) where you can eat whatever you want. The jury is still out for me on this approach but I’m trying it. Here are a few other practices I’ve implemented:
No alcohol - I’m 500+ days now off the sauce. Sometimes it’s boring but it makes everything else in my life a ton easier so I’m sticking with it.
Tracking meals - for now, I’m tracking everything that goes in my mouth on an app called Carb Manager. I’ve done this before. It’s probably not sustainable long-term but I do find a strong correlation between tracking and eating healthy… basically it feels crappy to have to enter bad foods into the tracker. Here’s what my macro goals look like by the way if anyone wants to comment on them…. would love a second opinion on if this looks off. Mostly wondering about the Fat.
Net carbs: 102g, Protein 136g, Fat 150g
c. A greater focus on minimizing saturated fat — I got over my skis last year in not worrying about fat at all. I was doing kind of a keto style low-carb, high-protein diet, not shying away from bacon, cheese or red meat at all, and drinking heavy cream in my coffee. But then… my LDL cholesterol shot up from 90 to 138 in 6 months. No bueno. I think focusing on minimizing the saturated fat will bring that back down. We’ll find out in a couple months. Btw, at the risk of oversharing, here’s a spreadsheet where I track all of my metrics in case you’re interested.
d. Adding more lean protein into the diet — I’ve recently started buying tofu… so there’s that. I actually like it, too. I’m eating lots of greek yogurt, cottage cheese, chicken, etc. And I’m trying to add in more legumes - things like chickpeas and black beans. And I’m about to start experimenting with some protein shakes, too, (and on the supplement side, creatine - if my stomach can handle it. Last time didn’t go well. This time I’m trying “micronized”… we’ll see!).
Finally, I’m keeping an eye on calories. My Whoop shows me how many calories I burn in a day (I’ve averaged ~2500/day over the last month for reference) so I think I want to be close to that in terms of what I consume - maybe at a slight caloric deficit because on balance I think I’d rather prioritize fat loss even though I want to gain muscle too. Again, if anyone thinks there’s a better approach here, let me know!
That about covers it! I’m doing a few other things, too, like:
Trying to prioritize sleep
Experimenting with some “two-a-day” workout schedules
Starting to learn more about stress management and particularly breath work…. more to come on this soon — trying to line up a podcast on this topic.
Hopefully it works out… I plan to be… well, not obese… later this year. We’ll see if I’m successful.
One final thought on everything I’ve written here. I think these two metrics: VO2 max and Body Fat % are fantastic measures of one’s actual health but incredibly they are not standard measures in a typical annual physical with your doctor. I had my physical in December — according to my doc, everything looked great outside of my cholesterol being a bit elevated (as mentioned earlier). He didn’t tell me that my cardio fitness has a ton of room for improvement. And he certainly didn’t tell me that I was obese… after all, I’m smack in the middle of the normal range for BMI. But in my view, this high-level, very general, non-detailed analysis is missing the point entirely. So therefore, I think if we really want to improve our health and hopefully longevity, too, we need to proactively take matters into our own hands. No one is coming to save us - especially traditional healthcare providers operating in an overtaxed system. So I’m getting started to make improvements. I’m optimistic that I can move the needle. I’ll check in at mid-year and at the end of the year to share how far I’ve gotten.
Oh, one more thing… common question: How much is it to get your VO2 max tested and to get a DEXA scan? It cost me $350 all-in for both which I had done at the same place. Google is your friend here in finding where you can do it if you’re interested.
Content Diet
Below is a non-exhaustive list of podcasts that have particularly influenced my thinking lately on all of the above:
Dr. Rhonda Patrick (FoundMyFitness) — The Longevity & Brain Benefits of Vigorous Exercise - This one really opened my eyes to the fact that I wasn’t doing enough intense exercise. I still love Zone 2 but I’m up’ing the HIIT workouts big time this year.
Dr. Rhonda Patrick x Peter Attia (FoundMyFitness) — Mastering Longevity - Insights on Cancer Prevention, Heart Disease and Aging. I’m a big Attia fan already (remember I wrote about his book Outlive?) and this episode did not disappoint. So, so much gold in here on all things health. Also, a great section for any women approaching or experiencing menopause. I sent this one to a lot of friends.
Tim Ferriss x Dr. Andy Galpin — Rebooting Tim’s Sleep, Nutrition, Supplements and Training for 2024 — I just like listening to two really smart and thoughtful guys on all things health and fitness chat about everything from optimizing sleep, to how caffeine affects your body to supplementation. Lots of gems in here.
Alright, my friend… that was a looong newsletter today. And you made it to the end! Thanks for sticking with me. I hope it added just a little bit of value to your life today.
See you in two weeks!
Greg
Got a great email back here from an IW reader and friend, Joe W.
Shared below with his permission. I thought it was super-helpful. - GC
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Hey Greg,
Really enjoyed reading this. Wanted to share some thoughts.
First, my wife is a primary care physician, and I totally agree with you on the healthcare system. I think she would too. It's wild to hear about her patients. The system is designed to keep insanely unhealthy people from dying sooner, not helping healthy people maximize their life and health span. It's really unfortunate. We basically need to do our own research and focus on the things that matter like VO2 max and body fat %. Luckily we have easy access to great information. I often listen to Peter Attia and Andrew Huberman with my wife so she can translate for me. She has high opinions of both of them.
Regarding your diet/body fat goals, I recommend checking out this Huberman episode. It's a little challenging to listen to, but it helped me understand nutrition better.
Like you, my cholesterol has jumped in the last two years. I go back in March for my annual physical, and if my levels are the same or higher, I'm going to try to get on a statin. This seems to be what Peter Attia recommends, and as long as it doesn't cause muscle pain, there really seem to be no other down sides. As you do, I eat pretty darn healthy, exercise 5-6 times per week, don't smoke, don't have high blood pressure, very rarely drink, and generally have no other risk factors. But if adding a statin is a no-risk way to stack the deck even more in my favor, I'm going to try it.
On VO2 max—this is something I've been paying attention to recently for the same reasons as you. I wear a Garmin watch which estimates my VO2 max at 53. I recently did the Cooper test (which was awful), and that put me around a 56. You basically run as fast as you can for 12 minutes and then plug your distance into a formula. I ran 1.89 miles in 12 minutes. It was so painful. Anyway, before doing this, I'd been doing regular VO2 max workouts for about a month. Once or twice a week I would do 4 rounds of 4 mins on/4 mins off on either an assault bike or treadmill. The 4 mins on are at the max effort you can hold for that time, and the 4 mins off I literally just spent sitting on the ground trying to get my heart rate back to 100. These workouts also suck, but I think they work. This is the protocol Attia recommends in his book (and on some podcasts).
I'm trying to get mine up to 60 this year. I think 45 is a great goal for you for this year, but I think you should continue trying to get it higher from there.
One other suggestion. I've been doing CrossFit for 2 years now, and I'm in the best all-around shape of my life. If you have any interest in this, I would highly recommend it. I can give you some pointers on finding a gym if you're interested. I typically try to do 4 CF workouts per week and run twice.
Sorry for the huge brain dump here. I love talking about this stuff. Happy to talk fitness any time you'd like. Good luck with your goals for the year, and thanks for sharing what you're working on. I enjoyed reading it!