I'm trying to find out why my heart rate goes so high during exercise or exertion. I very recently began running again, and while I acknowledge there is an element of unfitness here I don't think it explains the whole story.
My overnight resting heart rate is now around 60bpm with my sedentary HR about 70bpm.
With even slight exertion such as climbing the stairs, my heart rate goes up to 110bpm.
On a run a couple of weeks ago my HR climbed to over 200bpm. I appreciate that I haven't done any serious cardio work in 3years but I can walk for ages without a problem so I'm not sure it's it's entirely a fitness thing.
Is there a connection with hypothyroidism here?
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WitchingHour2point0
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Have you had your ferritin or an iron panel done recently?
Heart rate changes can often be due to low iron/ferritin which is extremely common with hypothyroidism.
You may also not be optimally replaced yet so your heart is working harder than it would normally, plus deconditioning issues.
When hypo we get low stomach acid which means we cannot absorb vitamins well from our food, regardless of a great diet. For thyroid hormone to work well we need OPTIMAL levels of vitamins. Have you recently or could you ask your GP to test levels of ferritin, folate, B12 & D3? Private tests are available, see link for companies offering private blood tests & discount codes, some offer a blood draw service at an extra cost. thyroiduk.org/help-and-supp...
There is also a new company offering walk in (includes free blood draw) & mail order blood tests in London, Kent, Sussex & Surrey areas. Check to see if there is a blood test company near you. onedaytests.com/products/ul...
Only do private tests on a Monday or Tuesday to avoid postal delays.
Do you have a copy of your latest blood results that you can share with us? You are legally entitled to a printed copy of your results, ask at GP reception. In England you can get the NHS app and ask for permission to see your blood results on that by asking at GP’s reception.
previous to that on 125mcg levo and 20mcg T3 were:
TSH: 0.02
FT4: 18.3 (12 - 22)
FT3: 5 (3.1 - 6.8)
In July Vit D was 107 (>50) and ferritin was 98 (13 - 150) but that was actually up from 75 in January.
In January B12 was on the low side at 81 (37.5 - 188), folate below range at 4.9 (8.83 - 60.8) I have been supplementing regularly since then so I'm anticipating they will have improved as they usually do once I'm supplementing. (retesting all next week)
Iron panel looked ok last year. Attached.
Edit to add: I'm late 30's but perimenopausal too. Waiting to start HRT shortly.
Thanks for helping me unpick things! Tests are always done in the same way. I split my dose of t4 & t3 in two. One when I get up, the other around 2:30 in the afternoon.
I test at 7:30 in the morning, so while not as suggested on here they're all done the same way so they're comparable.
I wanted to up the levo after the previous test but private endo said to up t3.
I started levo in summer 2020 and I've never found a stable dose. If I felt ok on a dose and tried to leave it longer than 8 weeks for an increase by 12 weeks I've been symptomatic and bloods have borne out that I needed an increase.
Suspect female hormones are impacting things; Oestrodial below range and FH above range, LH is creeping up to and now 80% through range.
I just worry about my heart rate - when I realised I'd gone above 200bpm I just walked home fearing I'd have a heart attack! Didn't feel that bad in my body though.
I'm doing bloods on Monday next week ready for my consultant appointment so I'll have a better view of where I sit next week in terms of dosing. Hoping to start HRT next month so that will change things again.
I'm not yet optimal but I'm not far off, I don't think. I feel great! Certainly compared to where I was in 2020.
How quickly does your heart recover after exercise? The fitter you become, the shorter this time elapse will be.
Personally, I wouldn’t push yourself to go more than 220 minus your age for any significant period. In a spin class I sometimes push myself, but only for short bursts. I’m also mindful to monitor how long it takes for my heart rate to drop back to my normal range.
As Jaydee1507 has said, it would be useful if you could share your thyroid and key vitamin tests with us.
Be mindful not to over exert yourself; little and often is a good fitness mantra!
Without recent thyroid blood test results it's almost impossible to comment, but...
It could be that you are undermedicated and your system does not hold enough hormone to support the extra exertion.
If thyroid hormone level is low ( particularly the active hormone T3) then metabolism is also likely to be slow and if metabolism is slow energy levels and stamina suffer....particularly during endurance type exercise.
As you exercise, your heart contracts faster and increases blood circulation, resulting in oxygenated blood, reaching the muscles more quickly. As the body moves, it requires more oxygen; hence the heart will have to meet the demand by pumping more blood, which increases the heart rate.
The heart needs a great deal of T3 to function well so another reason to have a full thyroid test to include...
TSH, FT4, FT3, vit D, vitB12, folate, ferritin and thyroid antibodies TPO and Tg if not akready tested
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