Exercise, Sweating, Pregnancy & the Glow

There are many things to look forward to when you become pregnant but one of the all time favorites is the celebrated pregnancy GLOW.  You can thank your glow to the increase in skin blood flow and hormones that makes your skin look radiant pink.  The mom-to-be literally radiates heat to everyone and everything around her, warming them up and thus allowing her to dissipate heat more efficiently.


Pregnant women who exercise regularly improve their ability to get rid of excess heat and better manage heat stress then non-exercisers.  It is a myth that pregnant women who do vigorous exercise are at risk for overheating and putting the baby at risk.

According to James Clapp III, MD, scientific evidence has shown that during pregnancy, a woman’s body adapts to regular exercise and excess heat more efficiently than a pregnant woman who does not exercise.

Reasons include: your core body temperature and set point for sweating decreases, triggering sweating sooner to dissipate excess heat.  When a pregnant women’s core temperature starts to rise she begins to sweat.  Hormones increase blood vessel dilation which brings blood flow to the skin allowing heat to pass through the skin.  Pregnant women also breath in 40-50% more air which improves her ability to release heat through expiration. This reduces the risk of the mom’s body temperature getting too high, that it will put the baby at risk, by getting rid of the heat though her skin and lungs.

The additive effect of exercise during pregnancy increases a women’s ability to both dissipate heat and store it.  Her ability to tolerate heat stress improves by about 30% in early pregnancy and as much as 70% in late pregnancy.  (James Clapp III, MD).  The risk of overheating is thus very low unless the exercise is intense, long in duration, and in extremely hot and humid weather.

Proper hydration and workout conditions are essential to keep the baby and mom safe.  Drink water all day and during exercise to keep your urine virtually clear.  Do not run or exercise outside in hot and humid conditions.  Make sure there is adequate air flow and moderate to mild temperature.  If exercising indoors, make sure there is good ventilation with fans, AC, or open windows.

Amy Anci