Average morning walk pulse rate lower on an empty stomach

[StaffanC]

Dear all, 

I'm a 65 year old Swedish male who takes a brisk walk, 9km, every morning. I would normally walk a speed of 10-11 minutes per kilometer. Same same every morning. Normally I get out some 30 minutes after breakfast. Using my Fitbit Charge 5, I have been keeping track of hearth rate for quite some time now. Normal average pulse rate after a 9 km walk would be 115 - 120 bpm with a maximum around 140-150 bpm.

To days in a row now, I tested to make the walk on an empty stomach. I had two mugs of coffee some 30 minutes before taking off. I did the same type of exercise two days (same walk time and same track) in a row and guess if I was surprised  when I checked the hearth rate values after each empty- stomach-walk:  average pulse rate was down to 90-95 bpm but the max pulse rate did not show any significate change. 

Question:  why on earth would the average pulse rate drop 20 bpm on an empty stomach ?  

Looking forward to hearing from the clever Community 🙂

Cheers,

Staffan

[JennyTheUnfit]

This is a fun observation.

I don't know, but my guess would be that if you just ate, your body needs to supply more blood to your digestive system. There is a myth that you shouldn't exercise after food as this starves your muscles of blood, but in reality it's fine as your body is perfectly able to provide blood to both your digestive system AND your muscles at the same time. But I guess this would require a higher heartrate to achieve?

[StaffanC]

Thanks for your comment, Jenny!

Cheers,

Staffan

[SebWotan]

I think something of the same. I always have a bump in my average heart rate after eating, lasting one hour typically, whatever the activity I am doing. I simply think this is because digestion requires energy. 

[emili]

Hi @StaffanC and welcome to the community. everyone is right on track with why your HR is lower without eating. I bet if you walked without the caffeine from the coffee, you would notice it would be even lower.