Actual MHR vs theoretical

Bordersroadie

I've been using a HRM for a while now and have just been using the default MHR for my age, in the absence of proper data. My goal, as a Sportiver is to get better at endurance and to improve hillclimbing with on-the-road intervals (ie lots of bloomin' steep hills!). I'm pleased to say that both things are improving a lot helped considerably by advice I've learned on this forum and other sources, about using the HRM data.

Having just done the Fred, I've discovered my true max I think!

I'm 48, so in "theory" (I know it's a crude method) my MHR = 220 - 48 = 172.

This weekend it went up to 181. I know this is an accurate reading, not an anomoly, because I've had several 179 readings in the last few weeks.

Now, I know the theory of HR says that your true max is higher when say running rather than riding. I'm in the process of debating whether or not to bother adjusting my MHR in the Garmin 500 setup to 181 from the current 172. If I do, should I really use 181 or is my true max higher since I did the 181 riding? Or just leave as is (172) because I've become familiar with in-ride monitoring of my % of max figure and what it means in practical terms, and what the hell if it's based on an inaccurate assumed MHR as long as I use the data correctly?

These are rhetorical questions, I'm not asking for an answer but just curious about others' experience of the same thing.

jibberjim

I think you're confused about theories. None of them are individual predictors, neither running being higher, your age being related or anything else. Don't use any of them, there's not any reason to know your max HR, which is good as there's no way you can guarantee you've achieved it in any particular test.

amaferanga

Use 181bpm. It's your best guesstimate so why would you use anything else?

Tom Dean

If you want to use a system based on MHR your should use your max for cycling. This may well be higher than what you have seen during a sportive - do a proper test.

jordan_217

Ever thought about getting a metabolic assessment? It will provide you with real-world data for your training zones, calorific requirements, Vo2 and training thresholds. Thus removing all the guess work, which is based on a 'one size fits all' rule of thumb.

The pre-programed training zones on my Suunto HRM were way off the data collected from a metabolic assessment. I realised that I'd been doing my 'hard' sessions too easy and my 'easy' sessions too hard. So I wasn't actually improving or resting effectively.

Once I had ascertained the correct training zones the benefits became apparent quite quickly.

Your training zones will probably vary for cycling compared to running, as running puts more stress on your cardio and aerobic system. For example, my HR zone 1 for running is 147-157 bpm but for cycling it's 117-127 bpm.

The person doing the metabolic assessment will be able to interpret the data and provide you with advice on structuring a training program to achieve your goals. You mention that your goal is endurance and sportives in particular, so increasing your aerobic efficiency would be the way to go. For me, this means working in zone 2 and low end zone 3.

A running and cycling assessment should cost about £100-120 and should ideally be done with a 48-72 hour rest in between, so your body has recovered. Though I've seen people offering cycling specific assessments for £60, which I think is relatively good value.

HTH.

ric/rstsport

It's quite possible for your cycling max HR to be as high *or* higher than your running HRmax depending on how well trained you are at cycling and whether you do any running. Just as it's quite possible for your cycling VO2max to be equal to, or higher than your running VO2max. Running does *not* place more stress on your 'cardio and aerobic systems'.

Basing your training levels on HRmax is fine and should be sport specific (i.e., if you're a multisport athlete you may well want running levels as well as swimming ones, or you may not).

Having some sort of maximal testing session (which should be sport specific and preferably with your own bike) can be a good idea. However, deriving training zones from such tests does not remove guesswork, because all training zones are arbitrary. Training happens along a continuum and there are no magic switches that take you from one training zone to the next.

HRmax using the 220-age provides an adequate way of determining predicted HRmax for groups of people, and has a significant variance for individuals which is not related to their fitness or much else. It's also likely that as you become fitter your HRmax will decrease.

To ascertain your HRmax you don't really need any fancy equipment other than a downloadable HR monitor (ha! try looking at a standard HR monitor at maximal effort and if you can see the numbers you're most likely not at max!). However, you do need to be healthy (unfit people can do maximal testing, but you need to be healthy) as maximal testing is extremely stressful, and can cause health related issues if unhealthy.

Ric

Bordersroadie

THanks for the advice, chaps, much appreciated.

topcattim

Ric/RSTSport wrote:

It's also likely that as you become fitter your HRmax will decrease.

Ric

Ah, that's interesting. I've never thought in detail about this before, but intuitively I had thought it would be the other way round - I had thought that as I get fitter, my heart gets able to work more (which I had defined as being able to beat more frequently) and therefore my max HR gets higher.

Not saying you're wrong as I have no other information on this, but I'd be interested in other's views on this?

racingcondor

Ric/RSTSport wrote:

It's quite possible for your cycling max HR to be as high *or* higher than your running HRmax depending on how well trained you are at cycling and whether you do any running.

This. My HR Max is around 179 but I've never been able to get it over 165 running. I put that down to my being a cyclist that occasionally runs while most people find the opposite because they run / play football etc and then take up cycling.

Use 181, you know you have hit 179 a few times and 181 now so it's as good as you'll get outside the lab. The Fred definitely has potential to push your heart rate up a bit...

Tom Dean

racingcondor wrote:

Use 181, you know you have hit 179 a few times and 181 now so it's as good as you'll get outside the lab. The Fred definitely has potential to push your heart rate up a bit...

No it isn't - MHR is very simple to test on the road or turbo.

If you are hitting your max in a sportive you must be pacing your ride in a very odd way IMO.