Advice on Lactate Threshold and VO2Max?

I think one of the drawbacks with these metrics is that it does not know "where" you are training. So if you train at sea level you are going to get "better" results than at altitude.

What is your max HR set to? Is that a value you have actually got to recently (or at least close to it)?

Ultimately though you can tell if you are improving or not in races or hard sustained runs. What are you seeing there?

I think one of the drawbacks with these metrics is that it does not know "where" you are training.

I'm not sure I agree it's an inherent shortcoming of VO[sub]2[/sub]'Max as a metric per se if measured properly in a lab, since altitude would affect both arterial and venous oxygen content.

The drawback lies only in using heart rate and pace to estimate VO[sub]2[/sub]'Max in the way consumer fitness trackers do it.

OK if I add "as implemented on these watches" you hopefully will understand what I meant...

I think one of the drawbacks with these metrics is that it does not know "where" you are training. So if you train at sea level you are going to get "better" results than at altitude.

What is your max HR set to? Is that a value you have actually got to recently (or at least close to it)?

Ultimately though you can tell if you are improving or not in races or hard sustained runs. What are you seeing there?

Thanks Tim. I am seeing improvement in times so I feel that my training is working. I am curious to understand why my vo2max value fluctuates. So my cycling vo2max is steadily creeping upwards over time. My running vo2max drops a little when I do speed training and picks up when I do a long slow run. Over time the trend is upwards, which is good, but the two steps forward one backwards on the dial for vo2max got me puzzled.

I too tend to see increases when doing long slow runs. It could indicate that we are "efficient" running sub maximally and/or it could point to a deficiency in the algorithm.

Ultimately though the best estimator of a parameter that is supposed to indicate how you can do in an maximal effort is at the highest intensities.

Day to day VO2 Max will change anyway as in a lab test you certainly need to be treat it like a race and be rested up for it. If the overall trend is in the right direction that is the most important thing... Also AFAIK the cycling VO2 Max tends to only "work" at higher intensities so it could be that it is only looking at days when you go harder.

Additionally, my weight has dropped (and is continuing to drop) so I would expect to see an increase in VO2Max?

Any ideas from the knowledgeable chaps out there what I am missing.

VO2Max has nothing to do with your weight or efficiency it is only to do with lung capacity (this is simplistic).

VO2Max has nothing to do with your weight or efficiency it is only to do with lung capacity (this is simplistic).

Well actually it is a function of your weight - see https://en.wikipedia.org/wiki/VO2_max

In a lab situation your actual oxygen uptake is divided by your weight. So if you lose weight but your oxygen uptake stays the same you will get a higher VO2 Max.

I too tend to see increases when doing long slow runs. It could indicate that we are "efficient" running sub maximally and/or it could point to a deficiency in the algorithm.

interesting, i never see increases after a long run or hard intervals. sometimes i see decreases after long runs though. increases for me usually occur after tempo/threshold runs or easy runs.

I also tend to see increases after threshold/near threshold runs.

Last week it was after a Hansons strength type workout with 6x1mi @HMP that totaled 12 miles with warm up and cool down.

Understanding VO2max (VO2peak)

Vo2max (more commonly VO2peak nowadays) is not meant to be an acute measure or indicator of fitness; it's meant to be looked at over extended time periods >6 weeks, usually after specific training programmes aimed at achieving specific outcomes. Also, any test to determine VO2max needs to be undertaken after a suitable period of recovery to ensure maximal effort can be applied, whether in a lab or otherwise.

In a lab setting VO2peak delivers output in L/min which is the absolute value and a measure of the body's ability to utilise oxygen for activity. Lung capacity does come into it, but more importantly it's how well the body can use the oxygen that counts - we inhale more oxygen than we can use. The metric commonly used is relative VO2peak which brings into account body mass and is the figure we are more commonly aware of and measured in mL/min/kg. So as Tim says, lose weight, maintain absolute VO2peak, gain relative VO2peak.

Algorithms used in our devices are based on hundreds of hours of research but can still only provide an estimate as there is no taking into account inspired or expired gases. Still, the numbers are sufficient to use as a guide, but not as a daily measure of fitness. The numbers need to be observed over time to see if they are falling, rising or maintaining. They will rise more quickly the less fit you are, for fairly obvious reasons, but they will plateau eventually. Your VO2 cannot continually increase. What you have to do is to work out how to increase the %age of VO2peak that you can use. The more of this oxygen you can turn into energy the further and faster you will go. That's why we do threshold training, under and overs etc. We're trying to push that %age up. That's why two people with identical VO2peak will likely have different performance outcomes - if one can operate aerobically at 70%VO2peak and the other at 80%VO2peak, it's clear who will win.

My advice would be to stop focussing on the VO2peak (VO2max) metric, other than checking on it's trend. Concentrate more on developing the ability to use a higher %age of your VO2 for exercise through focussed training programmes over periods of weeks.