Max heart rate

Bobblehatboy1975

Hello

Over the past month or so I've been struggling to reach my max heart rate. I've raced a fair amount this year in time trials in the summer and I've just finished the cx season. It's hard to say whether I'm getting any slower/faster because the cold weather slows you down, my cyclocross finish position has really changed. I've haven't changed my diet or been ill.

Has anyone else experienced this?

Is this my body telling me I need rest or is it something to do with the winter weather?

hdow

Max heart rate doesn't tell you much if anything about fitness apart from its a good idea to have one. Generally as you get aerobically fitter your max heart rate will reduce. Haemoglobin releases oxygen slower at lower temperatures. If your working muscles are colder because of the weather your blood will be chilled slightly and so release less oxygen, less oxygen burned means less CO2 in the bloodstream means the heart doesn't beat so fast.

Average sustainable heart rate is a useful thing to measure in races but power would be even better to monitor fitness.

Elevated resting heart rate can be a good measure of fatigue but heart rate variation is better

Bobblehatboy1975

Thanks for replying

'but heart rate variation is better'

How do I test for variation?

davebradswmb

Max heart rate does not change with fitness, what changes is the heart's capacity so for the same amount of effort the heart will beat more slowly, but then you should be able to work that bit harder until you hit your max heart rate limit.

ric/rstsport

davebradswmb wrote:

Max heart rate does not change with fitness, what changes is the heart's capacity so for the same amount of effort the heart will beat more slowly, but then you should be able to work that bit harder until you hit your max heart rate limit.

For clarity, max HR _does_ change with fitness, it decreases as fitness increases and vice versa. It's usual to see changes of up to 10 b/min.

Bobblehatboy1975

Ric/RSTSport wrote:

davebradswmb wrote:

Max heart rate does not change with fitness, what changes is the heart's capacity so for the same amount of effort the heart will beat more slowly, but then you should be able to work that bit harder until you hit your max heart rate limit.

For clarity, max HR _does_ change with fitness, it decreases as fitness increases and vice versa. It's usual to see changes of up to 10 b/min.

Yes my max heart used to be 174 now I'm struggling to get past 166.

keef66

Bobblehatboy1975 wrote:

Ric/RSTSport wrote:

davebradswmb wrote:

Max heart rate does not change with fitness, what changes is the heart's capacity so for the same amount of effort the heart will beat more slowly, but then you should be able to work that bit harder until you hit your max heart rate limit.

For clarity, max HR _does_ change with fitness, it decreases as fitness increases and vice versa. It's usual to see changes of up to 10 b/min.

Yes my max heart used to be 174 now I'm struggling to get past 166.

It also decreases with age. Mine has always been annoyingly close to the 220 minus age calculation, and I've seen it decline by 10bpm over a decade during which I've maintained the same level of fitness.

davebradswmb

Bobblehatboy1975 wrote:

Ric/RSTSport wrote:

davebradswmb wrote:

Max heart rate does not change with fitness, what changes is the heart's capacity so for the same amount of effort the heart will beat more slowly, but then you should be able to work that bit harder until you hit your max heart rate limit.

For clarity, max HR _does_ change with fitness, it decreases as fitness increases and vice versa. It's usual to see changes of up to 10 b/min.

Yes my max heart used to be 174 now I'm struggling to get past 166.

After I wrote this I was questioning myself and did some research (googling), and there is a lot of contradictory opinion, including HRM increasing with fitness!

From my own personal experience I judged my HRM to be 182 a couple of years ago and I have been working off that, but earlier this year I hit 184 in a club-run sprint. I know my fitness has improved over that period, at least in terms of my FTP and ability to ride for longer. I think that perhaps the reason for the difference between my experience and RSTSport's experience is that I am just a middle-aged club rider, maybe fitter than average but I am no racer, while RSTSport has clearly worked with proper athletes.

N0bodyOfTheGoat

For me, the idea of max heart lowering with improved fitness doesn't ring true. Over the last 23 months, my max heart rate recorded was 190bpm, until I hit 194bpm at the end of a turbo race two weeks ago. I could tell my legs were heavy during the warmup beforehand and the motivation of trying to stay ahead of the rider in fourth pushed me up the final ~2min climb to the finish.
https://www.strava.com/activities/2006855572/analysis

A few days later, I did my best power output for just under 20mins of ~302W, because I finished the entire route in 19mins44secs (sadly the app doesn't turn your rider around to then descend, which would enabled me to do a 20min+ effort).
https://www.strava.com/activities/2004978892

I'm now using an estimated FTP of ~290W, until I get around to doing a 20min+ virtual climb next week, after ~6 weeks of regular turbo training at approx 24C for up to ~90mins I've now pretty much adapted to knocking out power sessions that are the best I've done all year... But in fairness, I put the turbo away in early April and by around the end of June I stopped trying to beat my power PBs up outdoor cat3/4 hills due to the heatwave and not knowing where I could get free water topups.

I would agree that for me, I can now climb cat3/4s at low power with a much lower rate than I could in 2016. Going at my mate's pace on a ride back in September, I averaged under 138bpm for seven(?) different climbs, last year I don't think I climbed a categorised hill with an average under 150bpm.
https://www.strava.com/activities/1873113641

Not claiming any of the stats above are amazing (as is true for any time I put links to my rides), far from it, I've only been doing this fitness cycling for almost two years and turn 45 in a couple of days while coming from a very unfit and overweight baseline. Just seeing how far I can push myself until my body starts to crumble in a few years!

topcattim

In mid October, after a long season, I couldn't get my heart rate up to its max. I'd been noticing lower heart rates in general, and naively seeing these as signs of improved fitness - for example, I was doing a 45 minute effort at 13 bpm lower than previously. Turns out my body was just telling me I was knackered; a two week period of lighter training meant that I recovered nicely. For example, my max heart rate in a race at end of October was 7 bpm higher than in one in the first week of October.

Similarly, when I do the Tour of Wessex, 3 days of hilly long distance, by the third day, I can't get my HR up to the same elevated level as I can on the first day. Not because I'm getting better, but because I'm getting more tired.

So while a higher max heart rate isn't necessarily a goal to aim for in terms of training (I'd not previously come across Ric/RSTSport's point that max HR decreases with fitness, so that's news to me) if you find you can't lift your HR to its usual max, I'd see that as a sign of fatigue and therefore as a sign that you should take it easy for a bit.

darkhairedlord

davebradswmb wrote:

Bobblehatboy1975 wrote:

Ric/RSTSport wrote:

davebradswmb wrote:

Max heart rate does not change with fitness, what changes is the heart's capacity so for the same amount of effort the heart will beat more slowly, but then you should be able to work that bit harder until you hit your max heart rate limit.

For clarity, max HR _does_ change with fitness, it decreases as fitness increases and vice versa. It's usual to see changes of up to 10 b/min.

Yes my max heart used to be 174 now I'm struggling to get past 166.

After I wrote this I was questioning myself and did some research (googling), and there is a lot of contradictory opinion, including HRM increasing with fitness!

From my own personal experience I judged my HRM to be 182 a couple of years ago and I have been working off that, but earlier this year I hit 184 in a club-run sprint. I know my fitness has improved over that period, at least in terms of my FTP and ability to ride for longer. I think that perhaps the reason for the difference between my experience and RSTSport's experience is that I am just a middle-aged club rider, maybe fitter than average but I am no racer, while RSTSport has clearly worked with proper athletes.

Interwebs in contradiction shock!

davebradswmb

darkhairedlord wrote:

Interwebs in contradiction shock!

To a degree you are right, but there is some common factors that I gleaned from my googling:
Someone who is very unfit and unused to exercise will tend to increase their HRM as they get fitter, the most common explanation is that they simply get better at doing exercise and pushing themselves to the limit.
Reasonably active people will not see any change in their HRM.
Elite athletes may experience a reduction in HRM associated with an increase in fitness and in some cases it will be quite significant. I didn't find any explanation for this, but there is plenty of evidence that it is a real thing.

MishMash95

I've had something similar recently, my max is normally 206, and while it takes a really hard anaerobic 4-5 minute effort for me to hit that, I did used to hit it, even now just doing certain anaerobic intervals, I haven't even gone into Zone 5 HR (which for me is 200+). Not sure if its just the style of training, but having recently started a new job, I think there is just a bit of baseline tiredness.

Interestingly, my resting heart rate has done the opposite and has gone up. Normally it sits in the low-mid 40s when idle, however recently i'm struggling to get it below 55. Oddly, my training is going quite well at the moment, hitting good numbers for threshold and sweetspot style workouts and oddly, my HR for those kinds of intervals has gone down, but equally, my HR when riding at mid Z2 has gone up from 145-155 despite it feeling no different in terms of perceived effort.

Realistically, I have no idea what is going on and am just sort of rolling with it. I'm wondering if it's because I am doing more shorter rides, but with a higher frequency that i'm always carrying around that "afterburner" effect.

I think listening to your body is always the most important, and if you have another way to quantify performance e.g. power, then that can be a metric to determine whether you are overtrained or not. Could just be the weather, or could be your immune system being a little bit more fired up in the background (not necessarily ill, but your body will always be working to protect itself, and a lot more goes around in cold weather). For me, I'm only going to worry about it if the performance starts going through the toilet :S

neeb

My experience is that I record my highest HRs during hard efforts just after I've taken a few weeks off for some reason and lost fitness. However fatigue also seems to reduce maximum HR, but over a shorter time scale.

It makes intuitive sense to me that your maximum HR would decrease a little when you are fit - your heart actually gets bigger when you are fit (it's a muscle and responds to use). This will increase the volume of blood it can pump on each stroke (thus reducing the HR needed to move the same volume of blood), but perhaps it also simply can't beat quite as fast due to being larger - there is more tissue to contract and perhaps the contraction cycle at max just takes a little longer?

Bobblehatboy1975

topcattim wrote:

In mid October, after a long season, I couldn't get my heart rate up to its max. I'd been noticing lower heart rates in general, and naively seeing these as signs of improved fitness - for example, I was doing a 45 minute effort at 13 bpm lower than previously. Turns out my body was just telling me I was knackered; a two week period of lighter training meant that I recovered nicely. For example, my max heart rate in a race at end of October was 7 bpm higher than in one in the first week of October.

Similarly, when I do the Tour of Wessex, 3 days of hilly long distance, by the third day, I can't get my HR up to the same elevated level as I can on the first day. Not because I'm getting better, but because I'm getting more tired.

So while a higher max heart rate isn't necessarily a goal to aim for in terms of training (I'd not previously come across Ric/RSTSport's point that max HR decreases with fitness, so that's news to me) if you find you can't lift your HR to its usual max, I'd see that as a sign of fatigue and therefore as a sign that you should take it easy for a bit.

I think you're probably right, many thanks.

poynedexter

heart rate is a hard one to get your head round. your heart pumping is part of a system, with blood, arteries , veins, lungs, capillaries, muscles, joints, water, fuel (carbs etc) oxegyn etc, and all this operates within the context of your fitness levels, fatigue levels, and life in general.

your heart may pump slower as a response to fatigue/ lac of fitness elsewhere in the system or as a result of improved fitness overall (at the same power/ duration)

your max heart rate is your max. your ability to produce more power and how close you can operate (aerobically) close to this max is the key. if you are producing your power anaerobically then the clock will be ticking, so its important to raise the point (power and heart rate) at which you can tolerate and deal with lactate.