Dear Doctor,
I am a 35-year-old male from the UK. I recently made a number of lifestyle changes due to being overweight and having high-normal blood pressure (140/85). This has involved a lower-calorie, healthy balanced diet and a vigorous exercise regime (running 5k in 18-20 mins every lunchtime and cycling 15k every evening for the last 8 weeks). All of which has resulted in me losing 3 stone in about 3 months – I now weigh 12st 3lbs and my height is 5’9. I have also drastically reduced my caffeine and alcohol intake.
Today, out of interest, I measured my resting heart rate for the first time in those 8 weeks of exercise. The average over 5 readings was 50bpm. Eight weeks ago it was 75bpm. I’m slightly worried that it is too low, but I should add that I had a full medical including a cardio-respiratory test with ECG in April, and the ECG was normal. I also have no other symptoms of bradycardia.
1. Is 50bpm normal given that I am not a professional athlete and only started training 8 weeks ago after a semi-sedentary lifestyle for about 5 years until then (I was very fit in my twenties but not aware of my heart rate).
2. If there was another underlying cause for this bradycardia, would it have shown up on the ECG in April before I started my exercise regime?
Thank you very much for your time!