Podcast 251 - When/How to do VO2 max if older?

This was a good conversation. When both Rob and Trevor said time above 90% VO2Max, I was left wondering if it meant power or HR? I know if I change the rest interval on hard intervals, average HR for the work intervals will decrease even if power increases. And the more rest I put in, the more time I’ll have near VO2max workload, whether HR or power. For this reason, I agree with Trevor that just measuring time above a specifed power level or HR probably doesn’t guarantee that a particular interval protocol produces better adaptations.

Another point Rob and Trevor both got to is when to do the intervals and how fast the adaptations are. I am particularly interested because I read about a coach who was recommending that older athletes do high intensity year round (but modify volume) because the adaptations may be slower and rebuilding capacity may take longer. The argument was that one didn’t want VO2 max to drop too much. I’m interested in the VO2Max interval recommendations for athletes over 50. I’m 59 and do a VO2 max session almost every week (30on, 15offx12x 3-4) based on this advice, except for transition periods. I’m presuming I get some neuromuscular work on the accelerations and the intensity work is kept at a baseline. However, I am wondering if I should stop this for extended periods to work on lactate threshold, or increase significantly for peaking.

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I think that means what it says - 90% of vo2max. Of course, none of us can test that so do intervals where you are huffing and puffing.

I recall that they debated the 90% of HRmax.

Personally, I can’t hit 90% of HRmax for a sustained interval. If I do a 3-4-5 minute VO2max intervals, I’ll 87-88% by the end of the interval. High cadence helps get the HR higher.

I’ve been personally wondering if there are VO2max “lite” intervals that give you 90% of the gains with some percentage less pain.

I’ve heard some coaches suggest alternatives like 40/20s, 30/15s. Another alternative is 60 seconds MAP effort followed by some minutes at threshold - so 5 minute hard start threshold intervals.

I’m 56 and the last time I did a VO2max block (3-4-5 minute) intervals, I was crushed and it required significant recovery.

Hi @jm1,

Great questions! I’ll pipe in with some quick answers, but I’m sure you’ll get a lot of discussion about this.

In the studies, they’re actually not basing it on power or HR. They’re connecting the athletes to a metabolic cart and measuring their oxygen consumption. Normally you can say that HR and oxygen consumption correlate up to VO2max, but that was one of the fascinating things in these studies - they were able to increase oxygen consumption without increasing heart rate.

But, heart rate is still going to be a better correlate than power. For example, if you do a set of fifteen 30 second intervals at a 100 watts above FTP, you’ll likely be hitting your maximum oxygen consumption by half way through, but the first interval, you’re not going to get anywhere close. However, according to power, all of the intervals were the same.

In terms of your second question, yes, I definitely agree that doing very high intensity work as we age is important. The reason is we start to lose our fast twitch fibers and become very slow twitch dominant. Makes us great in time trials, but not very explosive. Doing sprints and very short intervals will help maintain those fast twitch fibers.

That said, my approach is slightly different. On the bike, I still prefer to do the work that will build the best engine - such as threshold work in the base season. I might sprinkle in some sprint work, but overall, what I have the athletes do on the bike at that time of year isn’t going to do a lot to maintain those fast twitch fibers.

I protect those fibers by having my athletes do a fairly robust program of weight training and plyometric work. It’s just important to lift either heavy weights or to lift explosively.

Hope that helps!

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I did a lot of 30/15 work in 2020. The heart rate looks like one long interval rather than a set of 30/15s. To hit the same max heart rates with 30/30s the on interval has to be much harder (for me).

I guess centrally you could have same heart rate but the stroke volume increases. Thus more oxygen pumped out towards the working muscles. Secondly the ability of oxygen to get from the capillaries into the muscle cells improves in some way. Maybe it’s more easily able to diffuse through the muscle cells barrier in some way. Thus take up in muscle cell improves.

I’m not a physiologist !

I re-listened to this episode. I was wrong. They didn’t bring up HRmax. I believe Dr. Seiler has talked about 90% of HRmax in the past.

This episode got me thinking about doing intervals on an Assault-type bike (Schwinn Airdyne). Maybe a higher level of VO2max could be sustained for longer when incorporating the arms? I remember @steveneal mentioning that he used a similar technique in the CyclingGym.

In listening more, I also realized that the test protocol for the study could have used actual O2 consumption measurement when talking about time above 90% VO2 max rather than a HR or power level. My take away: probably I should add some 8 minute intervals to the diet because regardless of the time at VO2 debate, they are effective training.

@trevor When you say threshold training, do you mean time near LT2 with sweet spot and lactate tolerance or more time at LT1 building endurance? I’ve been a sweet spot optimizer for years due to time constraints, but I’m trying to find the patience to do more LT1 work.

Hello @AJS914 yes I used the airdyne a lot. Both at TheCyclingGym and with private clients (some at home, some came to the gym).

Had a lot of success with getting athletes to increase heart rate and respiratory rate without killing their legs. Athletes who had a tough time getting heart rate up on the bike (one was a National champ cross rider, among others)

I won’t be able to do intervals this week and post them but I will try and get on the bike, and the airdyne at similar heart rates and show the difference in vo2 etc…


HI @Phil,

We asked Dr Ronnestad about that and as I remember, he said there wasn’t a change in stroke volume. His guess was that there was something going on in the periphery - the muscles were able to take more of the O2 out of the blood (as you hypothesized.)

@jm1, good question - this whole “threshold” thing gets fuzzy because of all the different ways the term is used. In fact, in our episode this week, you’re going to hear Dr San Millan say that he doesn’t like the terms “aerobic threshold” and “anaerobic threshold” at all.

That said, I’m always trying to take the science and put it into useable terms. So when I get the “suggestions” part of the show, I try to use the language that’s more common among athletes. Generally, when a cyclist talks about threshold training, they’re referring to training around FTP or LT2. And that’s what I was suggesting for the 8 minute intervals.

Hope that helps!

Would doing you intervals on cobbles be a good substitute for a vibration plate?

[sarcasm on] The condition of our local roads would be adequate enough to act as a vibration pad. [sarcasm off]


There has been a decent amount of work regarding vibration in cycling

Mountain Bikes

We just need someone to marry the two parts of research together. Quantify the outside vibration and measure the oxygen consumption. I’m sure it’ll be higher, but I’m also sure that individual situations and conditions will dictate by how much.

I would like to know what my VO2 max HR threshold is. I’m 72 years old & my Max HR is approx 162bpm. When I do Aerobic Capacity Intervals on my trainer (no power meter), I go hard taking about 30/40 secs to hit Zone 4 & hitting Zone 5 (150 bpm)after about 60/70 secs. I assume I’m close to VO2 max at this stage in low/med Z5. So, holding that HR for the rest of the Interval.
Just as the heart reaches maximum stroke volume long before maximum heart rate, I’m assuming the body also reaches max aerobic capacity before, but much closer to, max HR.
There are many ways of working out LT2 or Lactate Threshold to define our individual HR Training zones but there doesn’t seem to be the same provision for AC HR apart from “bleeding from the eyes”.
Although I’m a really keen cyclist, I can’t see the point in using a power meter at my age/ability and rely solely on HR monitor & RPE. So I think I’m hitting my Aerobic Capacity, doing what I’m doing but nothing I’ve read or heard entirely confirms this. Should I be pushing beyond Zone 5.1-Zone5.3 or am I going too hard and should instead back off to the high Zone 4’s.
Would really appreciate any feedback.