Question about BMR

Ariyamama

I have lazy heart syndrome, because of that my heart rate very rarely goes over 140bpm. That being said I'm starting to wonder if its effecting my BMR. I started my new routine in November and between then and January 14th I went from 141lb to 125lb. That sounds great but over the last 3-4 weeks that scale has started heading in the wrong direction. I'm back up to 130lb. I've consistently, since November stayed under 900 cal a day and have worked out 6-7 days a week. I wear a heart monitor during my workout and have noticed that its dropping off more mid-workout so I wondered if anyone would know if that could effect my BMR. Today it dropped off while i was doing burpees to 38bpm to give you an idea. I have a BMI scale and its showing I've actually gained a full pound of fat even after doubling down with 700cal less than 100 carbs and less than 30 sugars a day. Can anyone help me figure this out?

fitoverfortymom

A lot to unpack here, but my first question is: How are you measuring your calorie intake?

Nony_Mouse

You are massively under eating, and massively overexercising for the number of calories you are taking in. My guess, fluid retention from jacked up cortisol from the stress you're putting your body under.

https://bodyrecomposition.com/fat-loss/why-big-caloric-deficits-and-lots-of-activity-can-hurt-fat-loss.html/

Ariyamama

I've been tracking the intake through the myfitnesspal app. Using barcodes on pre-packed foods like protein shakes or powder and adding meals I cook by ingredient and then saving it as a meal for ease later on. I have addison's disease so I don't make cortisol well. They have me on a replacement therapy but it's the bare minimum in dosage. That's part of the reason I'm trying to get in shape. The treatment plan for this disease has a diminished return.

KerrieA87

Have you consulted a medical professional about your diet and exercise regime, and if you have, have you been honest about how many calories you’re not eating and how much exercise you’re doing? I’ve had a look at bmi charts and unless you’re really really short you’d already be a healthy weight. I’d be concerned that you’re doing too much and risking harm to yourself by not taking in minimum calories

Sand_TIger

I think they aren't saying you are inaccurate about your food, but rather that you aren't taking in enough nourishment so it's putting your body under a lot of stress. Might be a good idea to talk to your docs about this one - especially since you have them to consult - because that heart rate sounds pretty darn low especially for a body that's under load.

lemurcat2

So as I'm following this, you have been eating 900 cals from November to Jan 14 (so 10 weeks or less) and during that time you went from 141 (which seems like it is either barely overweight or in the healthy weight zone depending on how tall you are) to 125 -- so a loss of 16 lbs, or at least 1.6 lb/week. That's a deficit of 750 per day, and given your weight and how fast you've lost even if 900 is a bit lower than reality you are eating at a serious deficit for your size.

Nony's suggestion that the current struggles are due to overexercise and undereating and water retention thus strike me as extremely likely.

To answer the original question, no, heart rate shouldn't affect exercise burn. The use of a HRM for steady-state cardio works NOT because heart rate is what matters for burn (in fact when someone is out of shape and so has a high burn easily it's misleading) but just because once a person is in okay shape it allows for a good estimate (but not for something like lifting or burpees).

Given your health conditions I would talk to a doctor and share the loss rate, your eating logs, and your exercise (or ask to talk to a dietitian). Your instinct to cut cals to an even lower (and even more unhealthy) level worries me, as does your statement that your health conditions are why you want to get in shape compared with what you are doing. Getting in shape in a healthful way does not involve weight loss as fast as possible when one is (or is close to) a healthy weight or eating 900 or fewer cals while exercising.

I would highly recommend talking to your doctor about this.

Luke_rabbit

Please contact your doctor sooner rather than later. You are not gaining fat on such a low intake, you are retaining fluids. Your cardiologist will likely want to check on that to make sure it isn't a heart issue.

Ariyamama

I should have mentioned I am VERY short. Im just under 4'8". As I'm at 35% now, was 38% body fat so according to the doctor I am "extremely obese". Measurements come in at 44BX34WX32H so I'm carrying a lot of it around the middle. My cardiologist suggested weight lifting (low stress on my heart) and a 850 to 1000 cal a day diet. They don't want me to eliminate carbs but rather focus on good fats and proteins. I've been doing weight lifting at the suggestion of the doctors, as it will help with the steroid weight gain. I don't have a follow up with my endocrinologist for another few weeks but the whole team is supposed to be talking to each other, I assumed all my doctors were on the same page.

Nony_Mouse

Ariyamama wrote: »

I should have mentioned I am VERY short. Im just under 4'8". As I'm at 35% now, was 38% body fat so according to the doctor I am "extremely obese". Measurements come in at 44BX34WX32H so I'm carrying a lot of it around the middle. My cardiologist suggested weight lifting (low stress on my heart) and a 850 to 1000 cal a day diet. They don't want me to eliminate carbs but rather focus on good fats and proteins. I've been doing weight lifting at the suggestion of the doctors, as it will help with the steroid weight gain. I don't have a follow up with my endocrinologist for another few weeks but the whole team is supposed to be talking to each other, I assumed all my doctors were on the same page.

Well that's all quite important information to have left out.

When did you start the steroids? Because aside from increased appetite (for some), they also cause fluid retention. Given your medical conditions, this is really something to discuss with your medical team.

lemurcat2

Nony_Mouse wrote: »

Ariyamama wrote: »

I should have mentioned I am VERY short. Im just under 4'8". As I'm at 35% now, was 38% body fat so according to the doctor I am "extremely obese". Measurements come in at 44BX34WX32H so I'm carrying a lot of it around the middle. My cardiologist suggested weight lifting (low stress on my heart) and a 850 to 1000 cal a day diet. They don't want me to eliminate carbs but rather focus on good fats and proteins. I've been doing weight lifting at the suggestion of the doctors, as it will help with the steroid weight gain. I don't have a follow up with my endocrinologist for another few weeks but the whole team is supposed to be talking to each other, I assumed all my doctors were on the same page.

Well that's all quite important information to have left out.

When did you start the steroids? Because aside from increased appetite (for some), they also cause fluid retention. Given your medical conditions, this is really something to discuss with your medical team.

Agree with this.

I'll add that although the new information about the height/dr recommendation makes the calorie goal less worrisome, it does make the weight loss seem even more aggressive -- 1.6 lb/week for someone very small is a lot. With that plus the steroids, my thought is still that we are seeing some water retention and not regain, and that lowering cals more is not likely to be a good idea. But I would recommend again talking to the doctor or a dietitian and would defer to whatever they tell you.

Ariyamama

I started the steroids about 8 years ago when they figured out I had addison's but since they've had to up my dose, with my size, we're entering liver damage territory. There is some concern that fat gain in these circumstances might be signs of liver issues.

PAV8888

I think you're well above our pay grade.

If your calories are accurately counted, given the timelines, I would think that non-fat related changes are there more likely culprits for your recent increase.

A fat gain of 5 lb over 3 to 4 weeks would indicate a surplus of more than 500 calories a day. Does this even seem remotely plausible? Not based on what you have stated.

A gentle reminder that dimensions change because of fluid retention just as much as because of fat deposits.

Fairly accurate body composition scans do exist at various money and health costs. Dexa scans are relatively commonly available. Under research settings even MRI and CAT Scans have been employed for detailed body composition imaging