Exactly this happened to me. My VO2max used to be 48, but after I had surgery and had to stop running, it dropped to 38 in a year or so. I still walk about 10k steps a day and use my bike instead of the car whenever possible, but it clearly isn’t enough to maintain it.
I’m about to start training again and add some running back into my workouts, and I’m hoping to regain at least some of that VO2max.
I’m about to have surgery and will be unable to exercise for a few weeks at least. I also had to stop exercising because of spinal disc problems (hence surgery) for a couple of months, and I could tell my conditioning absolutely collapsed. Muscle decline was even more stark. Just a couple of months ago I was doing very strenuous squats including jumping squats with a 45lbs weight vest, and now I’m winded after 5 minutes of bodyweight squats.
I have noticed that with advancing age (I’m 67), you decondition extremely rapidly. When younger I could stop exercising and the decline in exercise capacity would be quite gradual. Now I stop exercising and my conditioning falls off a cliff.
Now that the diagnosis has been made, and a surgery date set for late December, I’ve resumed some exercise specially modified to spare the spine, because I will be immobilized for many weeks after the surgery and I don’t want to emerge from this with sarcopenia and frailty. I’m trying to build up some reserve.
As has been observed, older people decline in stages. There’s an event, you decline some and regain only part of your previous physical capacity. Then there’s another event and you decline further and so on. The trick is to try to regain your full exercise capacity after an event. That is what I am determined to do. I may have to adjust my exercise protocol, but I must do all I can to get back to 100% of my previous capacity.
For example, right now I cannot jog for longer than about 10 minutes due to spine issues. So instead, I’m doing a series of “high knees” intervals. It’s incredibly taxing on your cardio, I at present cannot do more than about 15 seconds in an interval (with proper form and max effort). So I do about 5 of those a day. I’m hoping to gradually increase the intervals, so in a few weeks before the surgery I’m at least in better shape and not like a human jellyfish. We’ll see.
Bottom line: you must fight to get your VO2Max back to a higher level and not allow an event (like surgery) to permanently set at a lower level. With age there will be a gradual decline anyway, but you try to avoid sharp drop offs after forced episodes of non-exercise.
After surgery and recovery, that will be my challenge. I must get back 100% of my conditioning and muscle strength and power. I am absolutely determined to meet that challenge.
I’m 50, absolutely fit, feel decades younger, and a “simple” surgery set me back hard. It took me over a year just to rebuild my strength, and now I probably need another 6 months to get my endurance and VO2 max back. I totally get now how having surgery at an advanced age can basically wipe you out physically.
An interesting piece from this year’s BSRA conference was that exercising the day before surgery helped reduce the harm to fitness from surgery. Not two days before, however.
Looking at that graph, it seems the older you get, the less you benefit from exercising more than just enough not to be completely sedentary. I’ll save my time (as I don’t enjoy exercise and do so exclusively for health benefits), and do just enough to extract most of the benefits (roughly within recommendations) and bank the rest of the time to add to my actual “life enjoyment”. Ultimately, time is the only thing we can’t make more of, so each minute is precious. YMMV.
I wonder about that… to what extent are there diminishing returns in exercising as it relates to Vo2Max?
I’m not sure how generalizable that graph is above - or how representative it is (or of what group it is representative of?). Not sure of the source.
And I wonder, are the outliers just more intense or more regular exercisers, or is there something else like genetics going on… such as for this guy…
That guy seems to disprove the graph above. But working out for 3 hours per day is probably not on your plans.
Here’s a summary and analysis of the paper titled “How to Be 80 Year Old and Have a VO₂max of a 35 Year Old”(How to Be 80 Year Old and Have a VO₂max of a 35 Year Old, Karlsen et al., 2015).
| Variable | Value | Comment |
|---|---|---|
| VO₂max | 50 mL·kg⁻¹·min⁻¹ = 3.31 L·min⁻¹ | Very high for an 80-yr-old. |
| Max HR | 175 beats·min⁻¹ | Indicates relatively well-preserved chronotropic capacity. |
| Oxygen pulse | 19 mL·beats⁻¹ | Suggests large stroke volume and good cardiac output. |
| Skeletal muscle mass | 49 % of body mass | Unusually high muscle mass for age, supportive of high oxygen utilization. |
| Daily steps | ~10,900 steps·day⁻¹ | High daily volume of movement compared to peers. |
| Daily physical-activity time | ~2 h 51 min·day⁻¹ | Combined moderate + vigorous intensity activities logged. |
| Lifelong activity history | Farm work from youth, endurance and strength training across life | The background context. |
From the data in the paper, we can infer what level of exercise this person performed. Important to note: the paper does not provide a detailed training log with weekly hours at specific intensities for the last decades, so some inference is needed — but the measured objective data (daily steps, active time, lifelong training) gives us a solid estimate.
Key points to infer exercise level:
Therefore, a practical summary of the exercise level:
In short : This man was well above typical activity guidelines — around 7× the recommended moderate-intensity volume and 2× the recommended vigorous-intensity volume (in his 80s), plus high muscle mass, strong organ reserve, and lifelong training history.
Well, a graph like that is not pulled out of thin air. It represents human data, what a member of the human cohort can expect. That’s reality, even if we wish it were not so. Decline is the norm, even among athletes. Note, that athletes outlive the general population on average by only a small number of years, around 3 or so in most countries. But can you have exceptions like that 80 year old? Sure! But so what, it’s the vast majority that matter. Calmet lived to 122, is that someone to point to when speaking of even the most health obsessed among us? Is Calmet really relevant to us? Is that 80 year old? Or is that graph by far more relevant? You could make two lines in a graph, all those in numbers who play the lottery, and the second line all those who actually win the lottery. Which line do you think is more relevant to you when you contemplate buying a lottery ticket? Same here - I am not about to devote 3 hours a day, lol, hoping I’ll be lucky enough to get the same results after a lifetime of such exercise as that 80yo… and that’s before we even ask the really relevant question: is that 80yo going to live longer than the next 80yo who only exercises 5% as much as that guy… 3hrs=180minutes, 5%of180minutes=9minutes. I’m willing to bet that an 80yo guy who exercises 9 minutes every single day, will live just as long (and in reasonable shape) as that exercise fanatic 80yo genetic lottery winner. Yeah, thanks, but no thanks 
!
Paper:
I enjoy exercising, especially brisk walking or jogging outside in nature - it makes me energized (especially jogging) and clears my mind. Swimming is another enjoyment, especially in combination with sauna. I also like to skate at least once a week. What I don’t like is lifting weights or doing resistance training. Time is precious - you are right!
Worst graph ever. Could be a winner of a contest for the most useless and inscrutable graph with random numbers and colors the meaning of which is not labeled. Life is too short. Pass.
Ha, I was curious so I looked it up:
https://www.jacc.org/doi/epdf/10.1016/j.jacc.2022.05.031
Basically being fit makes you less likely to die.
Conclusions
The association of CRF and mortality risk across the age spectrum (including septuagenarians and octogenarians), men, women, and all races was inverse, independent, and graded. No increased risk was observed with extreme fitness. Being unfit carried a greater risk than any of the cardiac risk factors examined.
Do they provide definition of “fit” or “not fit”? (Didn’t read the study).
Yes, but of course “its complicated” 
In the paper Cardiorespiratory Fitness and Mortality Risk Across the Spectra of Age, Race, and Sex (Kokkinos et al., J Am Coll Cardiol 2022) the authors define levels of fitness (cardiorespiratory fitness, CRF) as follows:
Definition of fitness‐categories
In summary: “fitness levels” are defined relative to the cohort’s age‐ and sex‐specific distribution of peak METs: the lowest quintile (“least fit”) vs the highest (~98th percentile, “extremely fit”), with specific MET cut-points reported in the paper.
Caveats
The JACC paper’s fitness categories roughly translate to:
For your age group, if you can do a 10 or 11 minute mile this will cut your risk of dying in half. You’re going to have to run part of it.
Can do 1 mile for 13 min (walking/running). Need to improve 
Update: tried to improve and got it worse - 1mi @14 min and I did my best today 
(was windy and cold).
Though my Sit-to-Rise -no hands is 0 and Single Leg balance is 60+. Does it count?
