Thursday, July 3, 2014 | 2 a.m.
With days like these, when temperatures top 110 degrees, we try to justify living inside a hair dryer by reciting the well-used refrain, “Yeah, but it’s a dry heat.”
And in fact, that does make a difference, especially when compared with the humidity of the Midwest, East and South.
The reason boils down to sweat, explains Jack Young, a kinesiology professor at UNLV.
In a dry environment our sweat evaporates quickly, allowing us to cool off — relatively speaking. In high-humidity regions, perspiration doesn’t readily evaporate, so we don’t cool off. Then our discomfort mounts: without cooling off, we sweat even more, putting us at risk of dehydration if we don’t replenish our lost fluids.
But there’s a danger with rapid evaporation in a dry environment, Young warns: If we are not conscious of sweating heavily because it doesn’t linger on our skin, we might not realize how much body fluid we are losing through perspiration, putting us, again, at risk of dehydration.
When it comes to strenuously working — or working out, both environments — dry and humid — can interfere with the body’s ability to properly cool itself.
If you're going to be active and outdoors, Young suggests wearing light-colored clothing to resist the sun’s heat and drink a cup of water every 15 to 20 minutes.
Not maintaining a proper fluid balance can lead to illnesses such as heat exhaustion, heat cramps and more seriously, heat stroke.
Heat exhaustion is characterized by vomiting, fatigue and heavy sweating, while heat cramps are defined by painful muscle contractions. Those afflicted should be moved to a cooler area and given plenty of fluids.
Victims of heat stroke will often experience high body temperature, a weak pulse and in some cases, unconsciousness. Medical treatment should be sought.