trouble breathing in humidity

Bringing up an old thread because I have the same issue. I took an asthma test and it came back negative, but it feels how I imagine asthma would feel. On my 12 min warm up tonight it was hot and humid and I was taking full deep breaths. I was seriously worried I was going to not be able to breathe later on in the workout. I did a tempo thing with walking breaks and over the next hour it gradually became easier to breathe. Any ideas?

I don't have any ideas or explanations, but just wanted to bump the thread cuz I have the same exact problem. I basically feel like I don't even want to run at all in the heat and humidity because it feels so awful. Any insights would be fantastic.

Thanks.

Yes, just about everybody has problems breathing in high humidity. There is less oxygen in the air.

The solution is simple, although many won't do it or don't like doing it: go slower. Sometimes go much slower than you would otherwise in cooler, drier conditions. I find high humidity even in cooler temps to be harder to run in, but going slower feels OK. Not great if it's for a race, though but even for a race, pacing yourself according to the conditions is the best way to beat your competitors in my experience.

And early morning is more humid than the evening usually.

Some people seem to be almost immune to the effects though. None of my teammates ever really complain of how much humidity effects them. And I'm usually one of the last people to complain about things.

And if I go as slow as is necessary I'm running 830 pace, which isn't going to prepare me to race fast. I've found my own solution which is do 4 mins tempo 1 min walk/jog however many times. I'm breathing like I'm racing a mile but my legs don't feel that tired.

Run at night, or in the morning.

Racey gal wrote:

Yes, just about everybody has problems breathing in high humidity. There is less oxygen in the air.

Where does the oxygen go?

trying to figure this out wrote:

Racey gal wrote:

Yes, just about everybody has problems breathing in high humidity. There is less oxygen in the air.

Where does the oxygen go?

How can there be an increase in the concentration of water vapor in the atmosphere without a decrease in the conectration of the other constituent gases?

hah I do run at night, it's still really humid some days.

The water vapor fills the void space between the molecules of the ambient gas. Therefore, for a given volume, the concentrations of the gases remains the same with a corresponding increase in humidty

Smartypants wrote:

The water vapor fills the void space between the molecules of the ambient gas. Therefore, for a given volume, the concentrations of the gases remains the same with a corresponding increase in humidty

Space between the molecules of 'ambient gas'? No. water vapor replaces dry air. Both the concentrations of nitrogen and oxygen decrease, and the absolute number of oxygen molecules decrease accordingly. The effect is lesser density of air.

trying to figure this out wrote:

Where does the oxygen go?

Up.

Less dense air rises. Warm air rises.

Dense air falls. Cold air falls.

malmo wrote:

trying to figure this out wrote:

Where does the oxygen go?

Up.

Less dense air rises. Warm air rises.

Dense air falls. Cold air falls.

That makes sense. And since cold air is more dense then cold air has more oxygen. And humid air is more dense, therefore humid air has more oxygen.

go it figured out now wrote:

That makes sense. And since cold air is more dense then cold air has more oxygen. And humid air is more dense, therefore humid air has more oxygen.

Humid air isn't more dense it's less dense.

"And early morning is more humid than the evening usually."

Not true. The relevant measure of humidity for a runner is dewpoint, not "relative humidity". Dewpoint is an absolute measure of how much water is in the air. Relative humidity is merely how saturated the air is relative to the temperature. Since cooler air holds less water before it will condense out, the relative humidity might be higher when the absolute humidity is not that high. Relative humidity is important for farmers and ascertaining drying conditions.

Let's say the temperature is 60 and the dewpoint is 60. The relative humidity will be 100% but that isn't nearly as humid as a temp of 80 and a dewpoint of 70 in terms of how much water is in the air.

Yes, humidity makes it harder to breathe as you are breathing in water vapor as a larger component of the air.

Brian wrote:

Yes, humidity makes it harder to breathe as you are breathing in water vapor as a larger component of the air.

But it does not mean there is less oxygen in the air.

There just just as much oxygen in the air when it's humid.

Good god, you know what I meant - it is the same as altitude - there isn't literally "less oxygen" there either. Humid (and hot) air is less dense than dry (or cold) air. The same proportion of oxygen, but less overall oxygen (because there is less of everything)

See this explanation:

"As air pressure decreases oxygen continues to account for about 21% of the gasses in the air as it does at sea level. But, there is less oxygen because there is less of all of the air's gasses...To see why humid air is less dense than dry air, we need to turn to one of the laws of nature the Italian physicist Amadeo Avogadro discovered in the early 1800s. In simple terms, he found that a fixed volume of gas, say one cubic meter, at the same temperature and pressure, would always have the same number of molecules no matter what gas is in the container. Most beginning chemistry books explain how this works.

Imagine a cubic foot of perfectly dry air. It contains about 78% nitrogen molecules, which each have a molecular weight of 28 (2 atoms with atomic weight 14) . Another 21% of the air is oxygen, with each molecule having a molecular weight of 32 (2 stoms with atomic weight 16). The final one percent is a mixture of other gases, which we won't worry about.

Molecules are free to move in and out of our cubic foot of air. What Avogadro discovered leads us to conclude that if we added water vapor molecules to our cubic foot of air, some of the nitrogen and oxygen molecules would leave — remember, the total number of molecules in our cubic foot of air stays the same.

The water molecules, which replace nitrogen or oxygen, have a molecular weight of 18. (One oxygen atom with atomic weight of 16, and two hudrogen atoms each with atomic weight of 1). This is lighter than both nitrogen and oxygen. In other words, replacing nitrogen and oxygen with water vapor decreases the weight of the air in the cubic foot; that is, it's density decreases. Wait a minute, you might say, "I know water's heavier than air." True, liquid water is heavier, or more dense, than air. But, the water that makes the air humid isn't liquid. It's water vapor, which is a gas that is lighter than nitrogen or oxygen. (Related: Understanding water in the atmosphere)."

The main reason one has the sensation of a higher respiration rate at a given pace in warm, humid weather is probably just because there is less blood volume available to working muscles, so you have to breath more to supply the same amount of oxygen. The net effect of the less dense air is probably not nearly as great as that.

Brian wrote:

Good god, you know what I meant - it is the same as altitude - there isn't literally "less oxygen" there either. Humid (and hot) air is less dense than dry (or cold) air. The same proportion of oxygen, but less overall oxygen (because there is less of everything)

"

You're not quite getting it right Brian. There are literally fewer oxygen molecules per unit of humid air versus that of dry air. Accordingly, the proportion of oxygen in dry air is higher than the proportion of O2 in humid air.

In normal conditions there is anywhere between 0 and 4 percent water vapor. Generally, in most places it's 2-3 percent. If there is enough energy in the air water vapor will replace dry air. When it does the percentages of the component gasses (relative to whole air) drop. The proportion of Nitrogen and oxygen relative to each other will remain the same.

Got it?

malmo wrote:

trying to figure this out wrote:

Where does the oxygen go?

Up.

Less dense air rises. Warm air rises.

Dense air falls. Cold air falls.

1) Are you saying there is more oxygen in air at higher altitudes;

2) Brian is relating humid with hot vs dry air with cold, which seems to obfuscate which has the higher O2 or whether it remains the same;

3) Malmo are you saying cold air is more dense and yet contains less O2? It seems that more dense would mean more O2. What are you meaning by density, as you stated all air at the same temp and pressure has the SAME # of molecules, therefore the density should be the same.

It seems to me that the O2 in the air does not change significantly, if at all, due to water vapor in the air. A problem with higher dew points is that water is not able to evaporate from the skin for dissipation of heat.