What Causes Those "Workout Yawns?"

Hey Sam, I noticed the other day when I was working out, that I yawned 4 or 5 times. I had gotten a good night’s sleep the night before. What’s up with that? --Bronson

Hey Bronson. I get this question a lot. When you yawn, you are also stretching your neck and head muscles in order for the veins to constrict and move blood (and oxygen) more rapidly to the brain. This action is triggered by carbon dioxide or hypoxia.

There's really no definitive scientific explanation for this phenomenon. However, I did some research and found a few possible causes (and some fun, "yawn facts.")

The first hypothesis is that when a room builds up carbon dioxide, the carbon dioxide causes you to become sleepy, so you begin to yawn (even if you're not feeling tired).

Other explanations:

A recent theory is that yawning is how your body regulates its own internal temperature.

Some claim that yawns are caused by the same chemicals (such as serotonin, dopamine, glutamic acid and nitric oxide) in the brain that affect emotions, mood, appetite and other phenomena. As more of these compounds are activated in your brain, the frequency of yawning increases.

Some folks are actually superstitious about yawning! A few Christian sects believe that yawning is brought on by the Devil who "sends evil demons to enter a person's body when your mouth is open." (This is why some people cover their mouths when they yawn).

Other superstitions:

* A yawn is a sign that danger is near.
* Counting a person's teeth robs them of one year of life for every tooth counted. This is why some people cover their mouths when they laugh, smile, or yawn.
* If two persons are seen to yawn one after the other, it is said that the one who yawned last bears no malice towards the one who yawned first.

I hope this helps! --Sam

Does Chlorine in Tap Water Cause Cancer?

Hey Sam, I have heard through various sources that the chlorine in tap water can contribute to (or cause) cancer. Is this true or not? Thanks, Chad

Hey Chad. Some studies have shown a link to cancer but not always. Most of the large scale research seems to indicate that there may be a small increase in the rates of bladder cancer, especially in men.

However, many public health agencies, such as the WHO say that the existing studies are not sufficient to draw any conclusions and that chlorinated water is obviously much better for you than, say, nonchlorinated water.

The EPA also sets maximum levels for chlorine in tap water. Most cities in the United States fall far below the maximum levels.

Overall, some studies show a slighter risk associated with chlorine in the water, but the findings are not conclusive.

Ferris Bueller Got it Right

A year ago this month, I learned that my uncle, Jeffrey Dietrich Larsen, was in the end stages of a two year battle with cancer. An architect in the style of Frank Lloyd Wright, he'd discovered a large tumor on his right shoulder, so doctors wanted to amputate his right arm. Instead, he chose to sell his only asset, his home, and move to Houston where doctors at Anderson Medical Center fought (successfully) to save his arm, but he lost his life.

Today, I received the harrowing news from my friend Ralph of his mother's unexpected death. I didn't know his mom, but her death resonated with me, and many of us who know Ralph.

Not a day goes by that I don't stop and reflect on the majesty (and frailty) of life. Each morning, in the dark hours of twilight when I kiss my partner before leaving for work, I'm consciously aware that it could be my last opportunity to demonstrate my love.

In the film, Ferris Bueller's Day Off, Matthew Broderick's character makes the following observation:

"Life moves pretty fast. If you don't stop to look around every once in awhile, you could miss it."

I'd say Ferris got it right.

Get Motivated with Traineo

If you need help getting motivated to work out and lose weight, check out Traineo. It's a new website that lets you corral a team of up to 4 motivators to help you stay accountable in your fitness goals. You record your diet, exercise, and daily stats online, and Traineo will keep your motivators updated with your progress every week. A little accountability can go a long way towards keeping you focused and on track. (Courtesy of CThings.com)

Flash: Heavy Drinking May Speed Progression to AIDS

HealthDay News -- Heavy drinking may speed up the time to developing AIDS, possibly by damaging the immune system, new animal research suggests.

Reporting in the October issue of Alcoholism: Clinical & Experimental Research, researchers from Louisiana State University Health Sciences Center set out to determine how chronic binge drinking might affect the progression to AIDS.

For 12 weeks, they fed alcohol to 16 rhesus macaques (often called rhesus monkeys) for five hours, four consecutive days per week to simulate chronic binge drinking. They fed another 16 rhesus macaques a sucrose solution under the same conditions.

Then they injected eight of the rhesus macaques in each group with simian immunodeficiency virus (SIV), a virus that mimics what happens to humans affected with HIV.

The researchers found that chronic binge drinking accelerated the time to AIDS in the rhesus macaques infected with SIV, with the average time to end-stage disease decreasing from 900 days in the control animals to 374 days in those exposed to alcohol.

"Because SIV infection in rhesus macaques is so similar to what happens in HIV-infected humans, we can expect that alcohol would have similar consequences in humans," study author Gregory Bagby, professor of physiology and medicine, said in a prepared statement.

What's a "Healthy" Bodyfat Percentage?

Hey Sam! I'm a 32-year-old guy, trying to lean out for a "big finale" pool party this coming weekend, but I don't know what bodyfat percentage I need to be. What's a healthy bodyfat percentage for a guy? I really want to be "ripped" for this event.

It sounds like you have two questions: first, what's a "healthy" bodyfat percentage and second, what's a "ripped" bodyfat percentage.

In women, a "healthy" range is anywhere from 19% to 28%.

In men, a "healthy" range is between 14% to 18%.

Now, as I said, keep in mind that healthy and being "ripped" are two seperate things. To visibly see your abs while at rest, men need to be under 10%. Women need to be under 18% to be "ripped."

I hope that helps. Have a great time at the pool party! --Sam

Why is My Urine Cloudy?

Hey Sam! I just woke up this morning after a long weekend of dancing and partying, and my urine was cloudy. Can you tell me why this is happening, and what is the cause of this? --Jake, San Diego

First, I should say that I'm not a medical professional and so I cannot diagnose a condition. Cloudy urine may indicate a serious problem and therefore needs a prompt professional medical diagnosis.

That said, cloudy or milky urine can sometimes result from various changes in the urine. It may result from other symptoms such as blood in urine, proteinuria, urine substances or other causes of urine color changes. In addition, certain foods or drinks may affect urine consistency and coloration.

Another thing is to consider is that you might also not be drinking enough water. You should take your bodyweight and divide in half to determine the amount of daily water intake. For example, I weigh 234 pounds, so I should be drinking about 116 ounces of water per day. This equates to about 15 eight ounce glasses.

I hope that helps! --Sam