fragmented.ME …
illness & health ...

anaerobic threshold & ME …

I have realised for quite some time that adrenaline is clearly linked to my ME and PEM. And so this blog post has been a long time coming. It is also going to be a post that I add to as I go through the process myself and learn new skills to handle my illness. So in line with that, the blog date will be updated and the post will show at the later date, even though its original writing date is March 2021, and those who are subscribed will get emails each time the post is updated.


I did a fair bit of research regarding this matter. The most important piece of information that I found can be read by going to ‘adrenaline & ME …’on my site.

However, I also found lots of other useful and practical research, especially around managing ME using a heart rate monitor. The best of these can be read by going to ‘[sg_popup id=”3901″ event=”inherit”]HRM-Factsheet[/sg_popup]’. And ‘[sg_popup id=”3905″ event=”inherit”]PEM Timecourse Factsheet[/sg_popup]’ and ‘[sg_popup id=”3906″ event=”inherit”]Energy Saving Factsheet[/sg_popup]’.

Using these above three documents as my main source of information (I even laminated them), plus my FitBit and making lots of informative notes on my iPad, I set myself a program off.

I Thought It Was Going To Be Easy

The Easy Bit …

[sg_popup id=”3918″ event=”inherit”]HRPacing ...[/sg_popup]

I already owned a Fitbit Sense and I downloaded an app to it, called HRPacing, which is free. I set the app up accordingly, based on my age, which is done automatically if you have the information already in your FitBit account, and I used the anaerobic threshold at 0.5% option (in line with guidance around severe ME).

I was all set up and ready to go. The only thing you need to realise, which at first I didn’t, is that the app needs to be kept always active on the Fitbit for it to work. this uses extra battery and my battery charging cycle went from 5-6 days to 3+ days. But it does work. In fact it works really well.

The Hard Bit …

When I first switched the app on, I had this fancy idea that I could just run with it and that would be it. I figured that each time when it vibrated, to warn me I was in anaerobic state, I would stop what I was doing, rest and recover, and then once I was recovered I would carry on with whatever I had been doing.

Ha ha haaa … bloody HA!

That was incredibly naive of me and also a good indication as to why I am as sick as I am. And so I had to tweak my ideas on things. Because I couldn’t stop, sometimes I would make myself extremely poorly in order to finish a task off, even with the physical symptoms and my FitBit vibrating incessantly on my wrist. Still, I would carry on …

A Process Of Elimination

I quickly realised it wasn’t going to be as simple as I thought. The watch seemed to be vibrating at me all the time. Especially when I was doing things I felt I couldn’t just stop in the middle of. But that is the nature of the beast we are dealing with here. ME is I relentless and equally as u forgiving.

So, I decided that I would first have to work out what I could and couldn’t do. I would need to find out what activities raised my HR to an anaerobic state and which didn’t. This wasn’t about a simple acknowledgment of HR in relation to what happened when I did the things I felt I needed to do. It was about really knowing what was going on, what happened to my HR, when it happened, and for how long it happened too. For instance, did my HR gradually rise, or was it instant, like when I stood up, and once my HR was risen did it stay high, and for how long after I stopped the activity did it stay high.

The most important thing I had already accepted was that I knew, for sure, living like I was now was certainly what was keeping me ill and gradually making me worse. I just needed to find out the impact each activity was having. Then the hard bit, I needed to change accordingly!

What I Regularly Do

My plan was to first carry on as I would normally. To document as much information as would be useful. Then determine which activities could be negotiable, those which could be done differently, and those that are simply non-negotiable.

What I’d like to point out here is, I don’t really do that much. My life is very far from what I would like to accept it to be, and even further away from what it has previously been. I’ve pulled back on so much because of how sick I am. That said, because I’m getting sicker all the time, I really don’t have a choice but to take this seriously. I feel that if I don’t there’s only one way this is going to end.

Below is a list of the things I do most days and anything I do regularly. There may be things I do infrequently that aren’t mentioned here but that’s because I only ever do what’s absolutely necessary. And I’m still getting sicker.

  • Wake up and take my pain medication.
  • Go to the bathroom and then get back in bed and just lie there, usually meditating, while my tablets work (usually about an hour).
  • Go downstairs and make myself a latte to bring back to bed and if I’m well enough I’ll open the blinds (there’s a gorgeous view from our bedroom window). I will check my messages, email, this website and Instagram at some point too.
  • About an hour later I get up. Go to the bathroom and change my smalls (who am I kidding … my BIGS). I brush my teeth (half the timer time on the toothbrush (1 1/2 minutes I think).
  • I don’t get dressed unless I’m going to a medical appointment, which I avoid at all costs. Every other day I change my PJs. Once a week I am to bathe and wash my hair, though in reality it’s more like every ten days (17 days is the longest I’ve gone).
  • I then go back to the bedroom and make the bed, if I can. That said, during lockdown my husband has been doing it most days.
  • I then go downstairs with my bag of necessary stuff (more about that bag later) and I put my cup and any other pots in water to soak.
  • I go to the settee and lie as flat as I can because by this time I’m already totally exhausted.
  • Once I’ve recovered enough I’ll get my iPhone or my iPad, or even my kindle, out and so some mental work.
  • My digestion is appalling so I only eat when I’m truly hungry, but if I get hungry during the day I only ever eat easy food like microwave stuff, bananas, and dry crackers. ..
  • My husband makes tea for 18:00 every night.
  • We watch TV with tea for about an hour. Then turn it off till 21:00 when we watch another hour of TV. I can’t have too much TV as it makes me feel poorly.
  • At 20:30 I brush my teeth, for the full 3 minutes, and I floss. I do this downstairs in our little bathroom because I found by the time I got upstairs I was just to exhausted to do my teeth without triggering a load of adrenaline, which would keep me awake.
  • In between these times I may write blogs, which I don’t actually write, I speak into my iPad and it turns it into text. I proof read it as I go along and change things that it’s gotten wrong. Some bits that it turns my spoken word into can be really funny and have the potential to get me into trouble too. LoL … I would like to ask here that if you ever find any silly typos please let me know because it’s important to me for the blog to be the best it can be but I also have to work within my limitations, which will lead to mistakes.
  • I often get insomnia, even though I’m totally exhausted. I find this mostly happens if I’ve been especially exhausted and had to trigger adrenaline in order to do stuff. The price I pay is adrenaline I can’t get rid of and gives me insomnia.
  • I often realise I’m very hungry when I’m lay in bed trying to fall asleep. I think this is because I often don’t eat enough during the day. So I will get up, have a small bowl of cereals, or a few crackers, something light and go back to bed and fall asleep instantly.

What has become apparent is that I am, daily, living outside my energy envelope because I have PEM every single day. Some days extremely severely.

Starting Point

So, as a starting point, I began by noting down whenever my watch vibrated to tell me I was in, or above, my anaerobic threshold. I added bits of information around what I was doing and for how long I went into anaerobic state. If it was an activity I could stop, then I would stop, rest and recover, then return to the activity. But in reality it really wasn’t often that simple. Psychologically, I have this personality that can’t stop until the job is done. Another reason why I am so sick. And mostly I only do stuff that is absolutely necessary, or that I feel is absolutely necessary, and really it would take as much effort, or even more, to keep stopping and starting.

I even spent a few days completely ignoring the vibratory warnings, when I wanted to get something done. Yes, I did pay a price and felt super unwell again for two weeks for this. Two weeks of major relapse for reaching anaerobic threshold and staying there for less than 15 minutes. Phew that’s a very high price!

I really do have to change … and change fast …

It has been a huge eye opener knowing when I’m in an anaerobic state. I now need to work on S T O P P I N G  as soon as I feel the vibration warning. And also work on eliminating what I can. So really scaling back what I feel is absolutely necessary.

Below you see how my notes started off and you will also find some of my most important findings from this exercise.

  • coming upstairs for bed and brushing teeth (instead brush teeth downstairs at 20:45 every night : set Alexa reminder in lounge)
  • making my coffee first thing in the morning HR consistently reaches high 90s and making a cup of tea takes about 5 mins @ 90-105
  • making the bed takes about 5-7 mins @ HR 100-105
  • combing my hair takes about 3 mins (not combed since last bath) @ HR 120 (absolutely exhausted)
  • ate a croissant HR touched 85 but while digesting it HR continually buzzing above 85-90
  • had to get water to take my tablets whilst alrready above my ETA so HR is now flittering between 90–100 (and my muscles are shaking internally)
  • tea (as in food not drink) : HR over 85 while eating but I lay down after tea HR stayed under 81

How to refine this and start to at least be aware of my energy envelope is my next step.


Things are getting so bloody serious now. I’m getting sicker by the day so I’ve decided I really do have to stop when the HRPacing app alerts me..

Below you will see how my notes are becoming more refined and you will also find some of my most important findings from this exercise.

  • waking up raises my HR above AT
  • brushing my teeth raises my HR above AT
  • making myself a drink raises my HR above AT
  • sitting up sometimes raises my HR above AT
  • talking sometimes raises my HR above AT
  • laying down sometimes raises my HR above AT
  • even while I am asleep my HR can raise above AT (WTAF)

So the above tells me that I don’t really have full control over this HR issue. But there are some things that consistently raise my HR and maybe that’s where I need to start. And maybe I have to accept that stopping when my watch vibrates and tells me I’m in anaerobic state is simply what I have to do. And it’s clear that AT will be brought on by so many different things and my HR will respond differently on different days to the same things. And that’s OK. What’s not OK is to ignore it and push through.


YES … it is so not OK to ignore my HR rising and the other body signals I get in order to push through …

THIS (ignoring my HR and symptoms in order to push through) IS MAKING ME SICKER BY THE MINUTE …

It’s all OK …

Below you will see how my notes are progressing and you will also find some of my most important findings from this exercise.

  • there’s nothing I can do consistently that doesn’t raise my HR above AT
  • I need to pay attention to my HR not the activity
  • it’s OK to stop what I’m doing and start again if / when I can
  • it’s OK not to be able to start again and just leave what I’m doing
  • it’s OK to stay in bed, lay flat, if anything more raises my HR too high
  • I MUST accept everything as it is
  • and this is OK … it’s all OK …

 I  A M  E N O U G H  … and so are you …

My Final Conclusion

It’s impossible for me to pick a set of activities that I can consistently do and have my HR stay within the safe range. Because even sleep raises my HR, up to 90% of the night some nights. So I have to make my FitBit warnings god and let the warnings it gives me be the deciding factor on what I can and can’t do.

I know if I can also listen, and heed, how I’m actually physically feeling  too I can stay in the safe range. I just have this dreadful habit of being able to ignore how I feel until I’m at a way too serious point.

Making Progress

Although, this has been a very long winded circular experiment, I do feel it’s been worthwhile.

When I started out I knew in my heart I was seriously sick and really should be in bed mostly. But using the FitBit HRPacing app has confirmed this to me.

I accept it and I’m ready to move on …

What Next?

I’m going to spend lots of time perusing this information and trying to work out a plan of how I can accept where I am at in terms of health and ability and see if I can marry the two into a working ‘way of being’.

I have to stop so I don’t keep making myself sicker but I also have to feel independent and not like my life is not worth living.

I don’t want to be dependent on other people to take care of my personal needs … yet, that’s where I may be right now …

How To Accept

I think this will be my next step and I will write about it on my ‘how to accept the unacceptable …’ post, you will be able to read it soon.

 fragmented.ME xXx

My birth name is Denise, but I’m know as Bella to those who love me. I have a first class honours degree in education & psychology and a strong passion to keep learning and educating others ... I have severe ME/CFS and lots of other chronic illnesses and I started this blog as an expansion to my instagram page, where I advocate for chronic illness. I am married and have two grown up boys, or should I say young men. I have three gorgeous grandchildren, one boy and two girls. And despite being chronically sick and housebound I am mostly happy. 🥰