How Does Your Heart Know When To Speed Up and Slow Down?
Hello everyone, and today we are going to be discussing about a topic that came to mind while writing some articles and put me in a rabbit hole about how the heart knows when to speed up and slow down.
There are three key factors. Let’s break it down.
Your Brain’s Systems
So your brain can be divided into multiple systems, but we will talk about the sympathetic system and the parasympathetic system.
The sympathetic system is the flight or fight part of your brain, responsible for situations of stress or activity. Think of this like the gas pedal. It has various nerves that connect to the origin of the heart electrical system (the SA node) and tell it to beat faster.
Get Zain Shariff’s stories in your inbox
Join Medium for free to get updates from this writer.
The parasympathetic system is the reverse, it is responsible for calm situations. It is the brake pedal. It sends calm signals to the SA node telling it to fire a slower rate.
Chemical Sensors
Your brain has some sensors detecting the amount of oxygen that is in your blood. If there needs more blood flow, in the case of exercise or stress, it will tell the heart to beat faster. If it needs less blood flow, then it will tell the heart to beat slower.
Hormones
These are chemical signals and are released by a variety of glands in the body. Some hormones will enter the blood and get caught by “cell satellites” that will order faster or slower heart contractions. Take for example, adrenaline, the hormone that is for excitement or fear. It will enter the blood and get detected by the brain which will order the heart to beat faster.
And those are the three major factors pushing for faster or slower heart beats. The heart beats at a resting rate and does not need constant nerve signaling to perform contractions. But when things get tough or intervention is needed from other parts of the body, there are many systems that help out.
If you want more articles like this, make sure to follow. Comment your thoughts on heart rate increasing and decreasing. Make sure to clap to increase its appearance in search results. I have an email subscription to get an email every week on something really intriguing about human biology and bioengineering and with sprinkles of other stuff I have been thinking about. That way you don’t forget.
And that’s about it, I will catch you on the flip flop, I’m out, see yah!
