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Name: Addie
Status: Student
Grade: 4-5
Location: IN
Country: USA
Date: Winter 2009-2010

Does the size of a dog affect it's heart rate before and after a walk or run?

Hi Addie -

That's a big question, and the simple answer is that the size of the dog's heart generally relates to the size of the dog, and this has an effect on heart rate. Very broadly speaking, smaller dogs tend to have faster heart rates than larger dogs.

The other big factor that can effect heart rate is how much exercise a dog gets. Dogs that are very athletic often have slower heart rates than dogs that don't - just like people. Athletes, whether they are people or dogs, have hearts that are better conditioned than their non-athlete counterparts, so athletic hearts don't have to pump as fast.

This all being said, there are a number of disease conditions that dogs can get which effect their heart size, and this does effect their heart rate and the way the heart beats - but I think that's a bit beyond your question.

I hope that helps!!

Susannah, MS, DVM



Just like yourself on the soccer field, If you are a smaller person, you have to run faster to keep up with someone who has a longer stride And this results in a faster heart rate.

Sincere regards,
Mike Stewart

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