Why does pulse decrease when holding breath?

Question

Okay so I'm writing a lab report and I want to say it is because you are cutting off oxygen that goes to your muscles and you pump less blood, so your heartrate decreases. is this correct?

Answer 1

When you deliberately change your pattern of breathing (hold your breath or take deep, slow breaths), you stimulate the vagus nerve, which ennervates, among other things, the major organs in the thoracic cavity (heart and lungs). The vagus nerve has an inhibitory effect on heart rate, so when you stimulate it, your heart rate slows.

Answer 2

I would have to say no, cardiac muscle is different from skeletal muscle in that it never fatigues. I.E. your heart doesn't stop when it gets tired. Cardiac muscle also regulates its rate of contraction by nerve pulses and the other cardiac muscle around it, it is not like skeletal muscle which is regulated by oxygen levels.

The likely reason why your pulse decreases when holding your breath is that a build up of co2 occurs which causes a chemical signaling to slow it down.

Co2 build up also controls when you breath and is the reason why you can not consciously suffocate yourself.

Answer 3

yes it is