What happens to the body in a hot yoga class

It is often said that people with high blood pressure should avoid hot yoga. It almost seemed as though high temperature causes high blood pressure but this is not true.

I used to think that hot yoga (high temperature) was a direct factor for rising blood pressure. I was wrong. The causes of high blood pressure can be due to atherosclerosis (too much fatty materials in the inner walls of the arteries), aging as your blood vessels becomes stiffer, under regulation of your RAAS system (hormone system that regulates blood pressure and fluid balance), kidney failure etc. That said, high temperature is definitely not one of the factors of high blood pressure.

Let me talk you through how the body reacts during a hot yoga class and why people with high blood pressure are not suitable of this hot trend.

Being in a hot environment, the body temperature rises and there is higher oxygen demand. The heart rate increases in order to pump blood faster to the rest of your body. Tachycardia (fast heart rate) may occur and this is because:

  1. increase oxygen demand and resulting in vasodilation dilation
  2. increase in heart rate to maintain cardiac output

Therefore, a heart attack may be triggered or you may feel dizzy (lightheaded) due to sudden vasodilation and dehydration (explained in the next paragraph) in a hot yoga class.

Perspiration then occurs to lose excess heat. Some time later, the body dehydrates and it lowers the blood volume. The kidney will respond by releasing aldosterone (a hormone to reabsorb sodium and water) as well as systemic vasoconstriction to increase blood pressure.

Thus, it is advisable to keep yourself hydrated through the sessions. Sipping on coconut water is great- it contains electrolytes that help hydrates the body. Also, keep your blood pressure under control before entering your hot class- you do not want your yoga class to turn into a star gazing session.

I hope this was somewhat informative and thanks for reading!

Clover/ YTTJan2016 (Weekend)