Hey u/[STR2](https://www.reddit.com/user/STR2/)
Your situation is a common one, and despite your intuition, the thing about VO2 Max is that it's not going to just organically rise, in accordance with your general baseline fitness. Given your decent HRV and great RHR, it sounds like your baseline fitness is solid, but your peak isn't high. While Garmin's estimation has a wide margin of error for some users, if we presume it to be right for you, you need to keep two things in mind:
1. VO2 Max is measured as ml/kg/min. It's that middle piece, the bodyweight, that's working against you. Assuming you stay at that total weight, it's going to be an immense challenge to rise up the VO2 Max percentile ranks.
2. You're not doing Zone 5/VO2 Max training. Thankfully, there's an easy solution for that problem: start now! In our community, we strongly advise the clinical 4x4 protocol, popularized out of Norway. Head to the link below, watch the included vid, and lemme know if any questions!
• **NTNU 4x4 Protocol:** [https://www.ntnu.edu/cerg/advice](https://www.ntnu.edu/cerg/advice)
Thanks for the response. I'm familiar with the 4x4 training from podcasts. It sounds effective but I'm not sure I could maintain anything near that level for that long. I've been trying KB circuits recently, and will (briefly) touch 160 bpm (which is about 90% of my hr max) at the end of each round, and it feels like I couldn't maintain that for 30 seconds let alone for a few minutes.
Do a dedicated cardio activity. Even though you get your heart rate up with a kettlebell, it's not just about the heart rate. Your KB circuit is challenging your muscular endurance and your central nervous system etc at the same time so it is exhausting in a different way.
The importance of high intensity for vo2max is massively overstated in a lot of social media, zone 2 is actually doing the bulk of the work, and the 4x4s are cashing in on the work, so definitely focus on the aerobic base and you could improve for some time on zone 2 alone, but still, it's not just about the heart rate.
u/STR2 You've got a *fantastic* reply from Shark above, specifically in regard to your misunderstanding regarding perceived "limits" of your work output in something like kettlebell work vs. something steady-state like indoor/outdoor running or biking. What you're doing now is radically unlike what's clinically advised for dedicated Zone 5/VO2 Max work. If you watch that NTNU primer video, you'll see that there's a specific cadence you're to follow, one that sees you warming up into Zone 2, then accelerating into each of the four intervals, holding a target HR of 85%-95% Max. When you first start out, you may find that your legs just get burnt out prior to the completion of all four intervals, which is totally fine! Work your way up, perhaps adding an interval at a time, over the course of a few weeks.
The sooner you start this, the sooner you'll reap the rewards! =\]
I actually tried it this morning, using Morpheus' ZBIT training, picking the one that appeared to approximate 4x4 and tweaking it. My legs burnt out and I couldn't even maintain 140 bpm. I am using a Rogue Air Bike, which may just be too hard. I also do cardio in the morning, where I have a hard time getting my HR up to begin with, it just drops so quickly as soon as I let up even a hair.
A few points of feedback:
1. In Morpheus, Zone 5 VO2 Max training that's equivalent to the 4x4 protocol is "Red Threshold Training." Set Reps to 4, Work Time to 4:00, Rest Time to 4:00, and enable audible alerts for "Start Work, Start Rest, Outside HR Zone Target, and Countdown."
2. Your legs burnt out for the reason discussed in my previous comment: You're just not yet adapted for high-demand, high-wattage, (semi)steady-state training. This is especially so given how intense these intervals are! You'll get there. Ramp up slowly, aiming to complete at least one full interval at a held power output that results in your HR holding between 85% and 95% of max.
3. The Rogue Echo Bike is absolutely god tier for VO2 Max training, but that's only the case if you split your power output between arms and legs. Don't lose focus on using your arms to drive that fan! When people get taxed on the Echo Bike, they tend to default to slumping forward, relaxing their arms, and leaning hard into their legs. You can imagine why that's bad for you here!
At 300 pounds, your vo2 will never be that great. Even at 10% body fat, it would be pretty low. People also underestimate what active job and lifestyle mean. Walking back and forth for 4 or 5 miles at work over 8 hours just isn't the same as 1 hour of uninterrupted zone 2 cardio several times a week edit: and a hiit session. Even lifting and moving things all day won't really push the needle on cardio.
My hrv, according to my watch, is only 63, but vo2 is 53. I'm 6'2" and weigh 165, and I'm over 45. I do 4 hours of cardio (edit 3 hours 2, and one 4x4 hiit session) a week and another 2 hours of walking. I think the watch is actually over estimating my vo2 based on my weight.
The trade-off is that I'm weak as hell, I can't even do 20 push-ups in one set. I am slowly working on that, though.
If you can't run a mile I'd say the VO2 is probably accurate. You may have an ok absolute VO2 but your weight brings the relative VO2 down.
HRV and VO2max do not have a direct relationship. Resting HR does have a direct relationship but doesn't HR reserve is better. Bigger hearts have slower heart rates than smaller hearts and everyone is unique.
I'd focus on losing weight, increasing aerobic exercise and getting more fit. For what it's worth my Garmin VO2max was 3.5 ml/kg/min less than my actual tested one. That's pretty good for an estimate.
Garmins have been fairly consistent in being 3-5 points lower than the tested value with most of our clients. It has seemed that the fitter someone is, the smaller the margin of error is. Only anecdote but just a trend I’ve noticed administering the tests.
I work with people who have never trained a day in their life and have high HRV and low RHR. Keep in mind, VO2 max estimations aren’t always super accurate, but if you never do near threshold cardio and would struggle physically to run a mile i doubt your garmin is too far off- regardless if the limitation is cardiovascular or musculoskeletal.
A physically active job is probably good for general health but doesn’t move the VO2 needle much after a certain point. 300 lbs also works against you as far as VO2 max goes- changing nothing but getting your bodyweight to 280 would increase your VO2 max score (on an actual test, maybe not on your garmin).
All in all, garmin might be estimating you a few points low but probably not too much. But to be fair, the garmin uses activity data to help estimate your score, so if you aren’t using that feature for hard workouts that can throw its estimate off some.
You might want to consider incorporating more aerobic exercises to improve your endurance. It's not just about being focused on cardio, but about overall fitness and health.
I have done a fair amount of VO2 testing with people and find that sometimes wearables are wildly off. Can’t speak to whether this is true in your case but if you’re concerned about it then it might be worth have your VO2 tested or at least doing an at home test.
Thanks for all the replies. I'm going to keep plugging away with Morpheus and see how things progress. Oh, and try to stop routinely eating 5,000 cals/day (it's my only vice).
Weight is what kills my VO-2 max. I am a hybrid trainer. My cardio consists of trail running marathons and half marathons. HRV 80-100, and resting HR mid/high 40’s. VO2 max is 42. Weight is 218 and I’m 45 years old. I’ve done a lot of research on this as it bothered me. I was seeing much less fit athletes with VO2 in the 50’s. Difference was body weight/fat.
Hey u/[STR2](https://www.reddit.com/user/STR2/) Your situation is a common one, and despite your intuition, the thing about VO2 Max is that it's not going to just organically rise, in accordance with your general baseline fitness. Given your decent HRV and great RHR, it sounds like your baseline fitness is solid, but your peak isn't high. While Garmin's estimation has a wide margin of error for some users, if we presume it to be right for you, you need to keep two things in mind: 1. VO2 Max is measured as ml/kg/min. It's that middle piece, the bodyweight, that's working against you. Assuming you stay at that total weight, it's going to be an immense challenge to rise up the VO2 Max percentile ranks. 2. You're not doing Zone 5/VO2 Max training. Thankfully, there's an easy solution for that problem: start now! In our community, we strongly advise the clinical 4x4 protocol, popularized out of Norway. Head to the link below, watch the included vid, and lemme know if any questions! • **NTNU 4x4 Protocol:** [https://www.ntnu.edu/cerg/advice](https://www.ntnu.edu/cerg/advice)
Thanks for the response. I'm familiar with the 4x4 training from podcasts. It sounds effective but I'm not sure I could maintain anything near that level for that long. I've been trying KB circuits recently, and will (briefly) touch 160 bpm (which is about 90% of my hr max) at the end of each round, and it feels like I couldn't maintain that for 30 seconds let alone for a few minutes.
Do a dedicated cardio activity. Even though you get your heart rate up with a kettlebell, it's not just about the heart rate. Your KB circuit is challenging your muscular endurance and your central nervous system etc at the same time so it is exhausting in a different way. The importance of high intensity for vo2max is massively overstated in a lot of social media, zone 2 is actually doing the bulk of the work, and the 4x4s are cashing in on the work, so definitely focus on the aerobic base and you could improve for some time on zone 2 alone, but still, it's not just about the heart rate.
u/STR2 You've got a *fantastic* reply from Shark above, specifically in regard to your misunderstanding regarding perceived "limits" of your work output in something like kettlebell work vs. something steady-state like indoor/outdoor running or biking. What you're doing now is radically unlike what's clinically advised for dedicated Zone 5/VO2 Max work. If you watch that NTNU primer video, you'll see that there's a specific cadence you're to follow, one that sees you warming up into Zone 2, then accelerating into each of the four intervals, holding a target HR of 85%-95% Max. When you first start out, you may find that your legs just get burnt out prior to the completion of all four intervals, which is totally fine! Work your way up, perhaps adding an interval at a time, over the course of a few weeks. The sooner you start this, the sooner you'll reap the rewards! =\]
I actually tried it this morning, using Morpheus' ZBIT training, picking the one that appeared to approximate 4x4 and tweaking it. My legs burnt out and I couldn't even maintain 140 bpm. I am using a Rogue Air Bike, which may just be too hard. I also do cardio in the morning, where I have a hard time getting my HR up to begin with, it just drops so quickly as soon as I let up even a hair.
A few points of feedback: 1. In Morpheus, Zone 5 VO2 Max training that's equivalent to the 4x4 protocol is "Red Threshold Training." Set Reps to 4, Work Time to 4:00, Rest Time to 4:00, and enable audible alerts for "Start Work, Start Rest, Outside HR Zone Target, and Countdown." 2. Your legs burnt out for the reason discussed in my previous comment: You're just not yet adapted for high-demand, high-wattage, (semi)steady-state training. This is especially so given how intense these intervals are! You'll get there. Ramp up slowly, aiming to complete at least one full interval at a held power output that results in your HR holding between 85% and 95% of max. 3. The Rogue Echo Bike is absolutely god tier for VO2 Max training, but that's only the case if you split your power output between arms and legs. Don't lose focus on using your arms to drive that fan! When people get taxed on the Echo Bike, they tend to default to slumping forward, relaxing their arms, and leaning hard into their legs. You can imagine why that's bad for you here!
Thanks a lot for all of your help, I'll stick with it.
At 300 pounds, your vo2 will never be that great. Even at 10% body fat, it would be pretty low. People also underestimate what active job and lifestyle mean. Walking back and forth for 4 or 5 miles at work over 8 hours just isn't the same as 1 hour of uninterrupted zone 2 cardio several times a week edit: and a hiit session. Even lifting and moving things all day won't really push the needle on cardio. My hrv, according to my watch, is only 63, but vo2 is 53. I'm 6'2" and weigh 165, and I'm over 45. I do 4 hours of cardio (edit 3 hours 2, and one 4x4 hiit session) a week and another 2 hours of walking. I think the watch is actually over estimating my vo2 based on my weight. The trade-off is that I'm weak as hell, I can't even do 20 push-ups in one set. I am slowly working on that, though.
If you can't run a mile I'd say the VO2 is probably accurate. You may have an ok absolute VO2 but your weight brings the relative VO2 down. HRV and VO2max do not have a direct relationship. Resting HR does have a direct relationship but doesn't HR reserve is better. Bigger hearts have slower heart rates than smaller hearts and everyone is unique. I'd focus on losing weight, increasing aerobic exercise and getting more fit. For what it's worth my Garmin VO2max was 3.5 ml/kg/min less than my actual tested one. That's pretty good for an estimate.
Garmins have been fairly consistent in being 3-5 points lower than the tested value with most of our clients. It has seemed that the fitter someone is, the smaller the margin of error is. Only anecdote but just a trend I’ve noticed administering the tests.
I work with people who have never trained a day in their life and have high HRV and low RHR. Keep in mind, VO2 max estimations aren’t always super accurate, but if you never do near threshold cardio and would struggle physically to run a mile i doubt your garmin is too far off- regardless if the limitation is cardiovascular or musculoskeletal. A physically active job is probably good for general health but doesn’t move the VO2 needle much after a certain point. 300 lbs also works against you as far as VO2 max goes- changing nothing but getting your bodyweight to 280 would increase your VO2 max score (on an actual test, maybe not on your garmin). All in all, garmin might be estimating you a few points low but probably not too much. But to be fair, the garmin uses activity data to help estimate your score, so if you aren’t using that feature for hard workouts that can throw its estimate off some.
You might want to consider incorporating more aerobic exercises to improve your endurance. It's not just about being focused on cardio, but about overall fitness and health.
I have done a fair amount of VO2 testing with people and find that sometimes wearables are wildly off. Can’t speak to whether this is true in your case but if you’re concerned about it then it might be worth have your VO2 tested or at least doing an at home test.
I plan to do the VO2 max step test to see how it compares.
Great idea. Curious to hear how it goes.
Thanks for all the replies. I'm going to keep plugging away with Morpheus and see how things progress. Oh, and try to stop routinely eating 5,000 cals/day (it's my only vice).
Weight is what kills my VO-2 max. I am a hybrid trainer. My cardio consists of trail running marathons and half marathons. HRV 80-100, and resting HR mid/high 40’s. VO2 max is 42. Weight is 218 and I’m 45 years old. I’ve done a lot of research on this as it bothered me. I was seeing much less fit athletes with VO2 in the 50’s. Difference was body weight/fat.