Using Heart Rate Monitor to detect 'starvation mode'!!

Options
Ok, so I don't like the term "starvation mode" - but it's what everyone uses on here. Anyway, my definition of starvation mode is what happens when you've been in a deficit too long and your body adapts and metabolism slows down. Of course there are many signs (cold, low energy, lower body temp, etc), but if you have a heart rate monitor and you know what your resting heart rate should be, this is another way to detect the so-called starvation mode.

To preface this: I was stuck at my weight eating at a deficit for quite a while. I have been spending the past 2 weeks on a full diet break (eating at or above maintenance level) while I was getting ready for my half marathon. I also haven't been training with my heart rate monitor because I've been taking it easy on my practices. Well today I used my heart rate monitor for the first time since the diet break and to my surprise my resting heart rate was an appropriate 58 - compared with my resting heart rate before the break - 45! I know my metabolism is burning hot right now and I just went back on a 250 calorie deficit. But I will continue to monitor my RHR and if it drops too low, I will know it's time for a refeed day.

Anyone else use their heart rate monitor for this purpose?

Replies

  • Tigermad
    Tigermad Posts: 305 Member
    Options
    Hello

    How does a lower resting heart rate point to starvation mode?
  • inspiration345
    inspiration345 Posts: 218 Member
    Options
    Oh I though the lower the RHR the better it is. You also burn more calories at activity when your RHR is low because it effects the vO2 max. My RHR is also very low around 55 BPM and I eat plenty so I am sure low RHR is not equal to being in starvation mode.
  • FairyMiss
    FairyMiss Posts: 1,812 Member
    Options
    mine is 73 so by your reasoning i should be burning like mad.


    not so much
  • fitaliciag
    Options
    45 BPM at a resting posture means you have extremely good cardio fitness. it does not indicate that your metabolism is slow. Where did you get that information?
  • olivia3263
    olivia3263 Posts: 263 Member
    Options
    Well, it might not be so for everyone, but it's a trend I've noticed in myself. Normal heart rate for my age is 60 - 80. Because I'm a runner, I'd expect my heart rate to be a little below 60 (yes, a lower heart rate does point to good health - especially in athletes), but for my fitness level is should be between 55 and 60. I wish I was fit enough to deserve a 45 rhr, but I'm not. When I plateau, my pulse drops about 10 below what it should be. I've researched this and when thyroid hormones are low (which can be caused by eating at a deficit) your pulse can slow down. I just know my body is working better now, and my heart rate has reflected this. It's not exact science, just a trend I've noticed for myself. If it's not true for everyone else, that's ok :)
  • ingies2011
    ingies2011 Posts: 127 Member
    Options
    This will be partly correct depending on how fit you are. For example an elite athlete will probably have a really low resting heart rate in the forties, but for them it does not constitute starvation mode. Anorexics also have really low resting heart rates, and low BPs, their bodies are trying to be really conservative with their energy expenditure, for them it is starvation mode. Then there are those people who have naturally low heart rates, or have conduction disorders causing low heart rates, or take meds that lower heart rates (eg betablockers).

    People who are losing weight and are getting fitter will also lower their resting heart rate, however if you find it getting really low like the poster above try to increase your calorie intake whilst maintaining your fitness, if you find that your resting heart rate does increase you probably weren't eating enough.
  • Uerzer
    Uerzer Posts: 273
    Options
    45 BPM at a resting posture means you have extremely good cardio fitness. it does not indicate that your metabolism is slow. Where did you get that information?

    +1


    No need to eat more to "exit starvation mode", just increasing exercise will do, because it increases your metabolism.
  • cherrieruns
    cherrieruns Posts: 342 Member
    Options
    I walk around with a heart rate around 45. FWIW I had actually wondered if this was part of why I have a hard time losing weight. Read anything I could find and the outcome is that a low heart rate does not impact weight loss/metabolism. I was a bit bummed by this because, well, I meant I owned the reason I wasn't losing weight - and couldn't blame something I had no control over.
  • olivia3263
    olivia3263 Posts: 263 Member
    Options
    This will be partly correct depending on how fit you are. For example an elite athlete will probably have a really low resting heart rate in the forties, but for them it does not constitute starvation mode. Anorexics also have really low resting heart rates, and low BPs, their bodies are trying to be really conservative with their energy expenditure, for them it is starvation mode. Then there are those people who have naturally low heart rates, or have conduction disorders causing low heart rates, or take meds that lower heart rates (eg betablockers).

    People who are losing weight and are getting fitter will also lower their resting heart rate, however if you find it getting really low like the poster above try to increase your calorie intake whilst maintaining your fitness, if you find that your resting heart rate does increase you probably weren't eating enough.

    This is exactly what I experienced! I kept my running the same, but increased my calories by about 1000 per day. I didn't gain any weight over the 2 weeks, but now my rhr is higher. My fitness level didn't suddenly decrease by that much in 2 weeks, so it must have been the eating more.
  • ingies2011
    ingies2011 Posts: 127 Member
    Options
    Another explanation could be that sometimes our bodies will do things to stop us from gaining weight (I know it sounds wierd but saw it on tv- hmm not the most scientific, however it was on BBC) so by increasing your heart rate you will be using more calories and maintaining your weight instead of gaining weight.
  • mangorabbit
    mangorabbit Posts: 219 Member
    Options
    Question for the OP (or anyone else who might know) are there other medically measurable indicators of 'starvation mode'/'conservation mode'/whatever the heck you want to call it?

    I ask as it seems I have always had a fairly low RHR, have had EKG's done at a couple points...would there be any indication beyond simply 'You have a low resting heart rate...maybe your body is in conservation mode...' ??
  • olivia3263
    olivia3263 Posts: 263 Member
    Options
    Question for the OP (or anyone else who might know) are there other medically measurable indicators of 'starvation mode'/'conservation mode'/whatever the heck you want to call it?

    I ask as it seems I have always had a fairly low RHR, have had EKG's done at a couple points...would there be any indication beyond simply 'You have a low resting heart rate...maybe your body is in conservation mode...' ??

    I think you have to experiment for yourself. I'm sure there are people who have a naturally low heart rate, but I do know that mine went higher - about 10 beats per minute - when I started eating more. And now that it's higher, I'm starting to lose again. It took a good two weeks eating a little above maintenance for it to get higher, but it did. I did a lot of research on hypothyroidism because my mom has it - I know I don't, but there are a lot of deficiencies that can mask it with the same symptoms (low body temp, cold fingers, low energy, low rhr, etc). Some things to make sure are: getting enough calories, iodine (but be careful with this one), fat (healthy fats and enough saturated fat, believe it or not - I use coconut oil or dairy from grass-fed cows, hormone free red meat, etc).

    I really think this is a good monitoring trick for me. I'm going to keep an eye on it, and if my rhr goes below 50 again, I'm going to take another diet break (I like those ;)
  • ingies2011
    ingies2011 Posts: 127 Member
    Options
    Low BP, feeling cold, tired, having no energy could all be signs.
  • Macatho
    Macatho Posts: 1
    Options
    I agree. When I'm on a ketogenic diet with like 500 kcal a day and train hard this is what happens:
    Normal resting pulse: 60-65ish
    Ketogenic diet on high exercise: 35-40ish.

    I bothers me a bit because I am about to take on an endevour and I dont want to drop below 35 in resting pulse, because that's when **** starts to go wrong. There are examples when extremely well trained athletes actually die in their sleep from having a resting pulse of 25.
  • yarwell
    yarwell Posts: 10,477 Member
    Options
    are there other medically measurable indicators of 'starvation mode'/'conservation mode'/whatever the heck you want to call it
    If you're looking for reduced metabolic rate then the simplest way is to actually measure your resting metabolic rate via respiration analysis - volume and gas analysis. The oxygen consumption equates to the calorie burn. Fitness centres may have the kit for this.

    Doubly labelled water does the same, but that's a bit more specialist and expensive.

    Reduced body temperature, less fidgetting, less physical activity are other signs.

    Some related reading - http://www.drbriffa.com/2012/06/15/exercise-boosts-the-metabolism-it-seems-the-reverse-might-be-true/ (the clue is in the URL)
  • ingies2011
    ingies2011 Posts: 127 Member
    Options
    bump
  • norcal_yogi
    norcal_yogi Posts: 675 Member
    Options
    45 BPM at a resting posture means you have extremely good cardio fitness. it does not indicate that your metabolism is slow. Where did you get that information?

    word...^
  • geekyjock76
    geekyjock76 Posts: 2,720 Member
    Options
    Question for the OP (or anyone else who might know) are there other medically measurable indicators of 'starvation mode'/'conservation mode'/whatever the heck you want to call it?
    Other signs of chronic caloric decrement in active females include: depressed Resting Metabolic Rate, history of amenorrhea, disruption in LH pulsatitlity and ovarian function, lowered leptin levels (metabolic hormones in general are imbalanced), osteopenia, reduced bone density, etc...

    http://jcem.endojournals.org/content/88/1/297.full

    http://jcem.endojournals.org/content/87/6/2777.full