Infrared Sauna Cardiovascular Health [2021 Guide]

First, your heart beats faster to bring blood to the capillaries just below your skin’s surface so sweat can be released through your skin triggering your body to go into the parasympathetic mode of your autonomic nervous system. This is your body’s “rest and digest” mode. It is the unconscious action responsible for transmitting sensory information from your body’s organs to your central nervous system. This transmission tells your body to relax.

Next, the opposing and complementary nervous system response is the sympathetic nervous system. This is the fight or flight response which tells your body to be alert and to act in the face of danger or challenges requiring quick responses. Your body must be in one mode, but not both, at all times.

Lastly, when your body goes into relaxation mode in the parasympathetic response, your blood vessels expand through vasodilation. Your nervous system tells your heart to pump faster and for your arteries, vessels, venules and veins to allow more blood to pass through. Blood pressure drops as a result.

While not the goal of this book, it’s good to know this: Blood pressure is best explained through the following analogy:

If your heart is a hand gently holding a bag of fluid with a straw leading out of it, the systolic blood pressure rate (top number when measuring blood pressure [120/80]) is the amount of resistance that the straw applies to the fluid when it attempts to leave the bag when squeezed. If the straw’s circumference is bigger, there is less pressure resistance, and if the straw’s circumference is smaller, the pressure is greater. The greater the pressure, the higher the systolic blood pressure number.

The diastolic rate (the bottom number [120/80]) is the amount of pressure exerted inside the straw (or arteries) during rest after the bag has been emptied through contraction through of the straw.