Monday, July 27, 2015

VO2 Max

The other day a colleague came up to me and asked me what my VO2 Max was. I couldn't remember whether it was just under 60 or just under 70 - but 70 sounded too high to me. It turned out to be 69 - although I've always felt that this was unrealistic - and he immediately responded by sending me back an excerpt from a Wikipedia article which put me on a par with Ron Hill, the second man to ever break 2:10 in the Marathon. But he reminded me that I last did that test 2 years ago, when I considered myself to be in such good shape that I wanted to take a "photo" of how I was for later comparison. How opportune because that was the same year I last ran the New York Marathon, so it seemed like a good idea to do another one to see how much of my perceived decline lately was in my head, and how much was in my lungs.

Strictly speaking, the lungs are only one part of what goes to determine your VO2 Max. Specifically, it measures how much oxygen (O2) per kilo of body mass you use to metabolize (burn) carbohydrates and fat when exercising, and this in turn depends on how much muscle mass with aerobic fibers you have, how many capillaries you have to transport the oxygen there and, of course, your lung capacity. It seems that these things are largely determined genetically - or at least your max VO2Max might be - and that training can only bring you closer to your max max. Having said that, only 6 months after giving up smoking and taking up running instead, I also recorded a VO2 Max of 68 (slightly less only because I weighed a bit more then) which was a factor in encouraging me to take it a bit more seriously.

Having said that, when I did start to take it more seriously, training with a coach, whenever I did VO2 Max tests with him, the number came out much lower - the best I got was 61 if I remember right. Of course, I find it hard to remember because I prefer to keep the 69 number in my head.

This time I expected to get a lower score but I specifically wanted to go back to the Reebok Sports Club where it might be exaggeratedly high but it would at least be a good reference relative to the score I got two years ago. It's true that I am not at the same point in a training cycle nor am I training as intensively right now, but I didn't expect to get 59 - 20% lower than last time. To make it even worse, I was about 3 kilos lighter so my VO2 Max would have been 3% bigger, all other considerations being equal. Maybe they have re-calibrated the machine or bought a new one? Or maybe its just not a very reliable test.

Another thing to look at is the maximum heart rate. This tends to drift downwards with age (I suppose in part because you tend to lose muscle mass and therefore have less to "feed" with oxygen) but as much as the commonly reported 1 bpm per year I have not experienced. Its true that I tend to avoid situations that take my heart to its limit as much as possible but I had it in my head that it must be around 190 bpm. In the test (which was supposed to take me to my maximum everything) I only got to 180 bpm! To be fair, this needs to be verified by looking at the electrocardiogram in detail - as usual, my profuse sweating through the machines off and the assistant had to keep adjusting the electrodes while I was running. At 21 kph!

That was the other surprising thing about the test. If my VO2 Max has gone down by 20%, how come I was running faster on less oxygen? The maximal velocity is called vVO2 Max and some people think it is more interesting that VO2 Max. Last year I did an experiment of hardcore interval training at my then vVO2 Max of 20 kph. Maybe that helped because it doesn't seem to have helped with anything else: I ended up breaking the board of my brand new treadmill in less than 5 months and I suspect that it has something to do with the appearance of my Morton's Neuromas, although the doctor in the Reebok Sports Club told me that it didn't necessarily have anything to do with it. So it would seem as though my running economy has improved by a factor of 120% * 105% (20% less oxygen/kilo for 5% more speed) - sounds good, right? What makes more sense is that my VO2 Max is right now and was significantly overstated before.

Well, I think it is important to look beyond the numbers, to what they are trying to tell you. Nobody ever won a race on their VO2 Max. (By the way, my new Fenix 2 watch has estimated based on a few easy runs that my VO2 Max is  - wait for it - 59 ml/kg/min! According to the watch, this corresponds to a Half Marathon in 1:21 and a Marathon in 2:49, times I would be happy to see again.). My conclusions are:

My maximum heart rate is not what it used to be. I will wait for the final report from Reebok but I may repeat the test (without the VO2 measurement) to see whether I can get up to 190 again (don't worry, I will stop before I literally kill myself). I should adjust the heart rate at which I plan to run my races - particularly the New York Marathon in November - accordingly. It might help explain why I have been going off way too fast (both in terms of pace and heart rate) and finishing disappointingly lately.

I should do more strength training. I stopped doing weight training a couple of years ago, thinking that it was better to do specific strength building exercises such as plyometrics, hill sprints and the like. It reminds me a bit of when, years ago, I decided it made much more sense to stop paying for Spanish lessons to instead practice Spanish with my then girlfriend (now wife) - of course, we never did... Now I don't do anything in the way of strength training. One thing about getting older that seems inevitable is that there is a tendency to lose muscle mass which you have to fight against. I guess the body needs more and more proof that you really need to carry around and feed all that bulk (shame it doesn't need the same amount of convincing when it comes to fat). (Actually, the doctor told me that I should consider increasing my fat as my level of 11% was considered to be on the low side, and that fat helped protect against illness among other things.) As New York is a relatively hilly Marathon, I will certainly do some hilly runs and hill sprints etc, but I think it is a good idea to do some work in the gym always being careful not to "bulk up" too much of course.

Apparently Red Bull is not good for you. It makes sense, I suppose, as it seems to good to be true. I had always thought that just as sex is not as bad for you as drugs or indeed rock 'n' roll, Red Bull didn't have to be bad for you. I remember once a friend forwarding an article from the British Journal of Medicine which  proved scientifically that Red Bull was bade for you - the only hitch being that it was faked. The doctor at the Reebok Sports Club wasn't worried about my one-glass-of-red-wine-a-day regime or for that matter the 4 espressos I have everyday, but she did balk when I confessed about taking one Red Bull every other day. Apparently Red Bull is not good for you, so I will stick to my promise and cut down drastically.

UPDATE: It turns out that they made a mistake and forgot to divide my VO2 Max by my weight, so it is in fact very similar to the last values: 68.63 ml/kg/min. My maximum heart rate turned out to be 185 bpm, significantly less than the 190 of two years ago but the weird thing is that - while my anaerobic threshold is more or less where it has always been (180 bpm) - my aerobic threshold is much higher (168 versus 160 two years ago, versus 155 bpm 7 years ago) and, of course, even higher in percentage of maximum heart rate terms. It certainly looks as though my heart has adapted to the training. However, one of the comments I received on the final report said that I was slightly detrained as the rate at which my heart returned to beating normally was much lower, but that is not surprising or indeed worrying, it is just a question of putting the work in.

I had started to get a bit paranoid about my VO2 Max being so much lower than last time, so I went to the gym for a weights session, which is probably a good idea anyway. I looked up the weights I was lifting last time I went - in 2012 (gulp!) - and allowed myself to slack off a little. But when I set the machine to 78 kgs, I found that I could barely lift it once, let alone 15 times! I put it down to 60 kgs in the end, and struggled through the set. Feeling really demoralized, I went to the next machine where I set the dial to 52 kgs and found that it was ridiculously easy! Hang on a minute, could it be that I got them the wrong way round? Doh! So 60 kgs was 16% higher than I had intended to lift! Writing this on my brother's computer in London, I am still feeling the pain on Sunday, 4 days after... In spite of having trouble sitting down or doing my shoelaces, I am at least able to run reasonably well. I've been enjoying exploring the area round his new house which is particularly conducive to running, not to mention the cool but sunny weather that has been accompanying me so far. Two more weeks of relaxed running before I start the countdown to New York... 


  1. I remember the squad all having our VO2 max measured back in my rowing days. We plotted it against 2K time and it was a completely random scatter diagram - absolutely no correlation at all. I lost a bit of faith in it as an indicator after that!

    1. Interesting... I wish I could remember my VO2 Max from those days. I remember having it tested at the British Rowing Association or whatever it was called, and complaining about not being able to breathe through my nose (they put a clip on it). They told me that it was physically impossible to breathe through your nose and your mouth at the same time so it wouldn't make any difference. I still don't believe them.

      But your comment made me think of an academic paper I once read that said that absolute VO2 was a much better measure (i.e., not divided by mass in kg) for rowers as the body weight was supported by the boat. Makes sense when you look at how much rowers weigh.

      Having said all that, I don't really believe in VO2 Max, especially when you realize that the sports scientists also look at "running economy" which, when combined with your VO2 Max just tells you your maximum velocity (you get back what you put in). In other words, everything that the VO2 Max can't explain (and therefore all that is interesting) is in this magic number of "running economy".

      How's your running going? Doing any marathons, time trials or the like?

  2. I'm still running - doing a bit of cycling too - but not really raced this year, just did one half marathon in spring, nothing since. I should really enter something to get some focus - in fact I was even wondering about another marathon! Which would you recommend out of NY and LDN if I did another? - both in terms of a good experience and trying to put down a decent time?

    1. Well, I can speak about London Marathon much as I haven't done it. It is probably faster as it is a flatter course I believe. But in terms of atmosphere and the course itself, New York is in a class of its own I reckon.