Pulse Oximetry, Blood Oxygen Saturation and Altitude Acclimatization

guest — Mon, 30 Jan 2012 23:51:25 GMT

For awhile, I’ve tried to determine if repeated short-term exposure to altitude can help with the acclimatization process. This curiosity is geared primarily for people living in a Front Range situation and then doing fun activities, training or racing in the mountains.

To help me determine if short-term exposure to altitude might help acclimatize people so that they can enjoy fun activities, training and racing at altitude, I picked up a pulse oximeter. I mentioned the pulse oximeter in a 2010 blog. My personal interest in the numbers is for alpine skiing, Nordic skiing, trail running, road cycling, mountain biking and hiking.

A pulse oximeter is a non-invasive way to measure the amount of oxygen the blood is carrying. The number displayed is expressed as a percentage of the maximum amount the blood could carry at 100 percent. At sea level, typical saturation values are 97 to 99 percent in healthy people. At 5,000 feet it might drop to 95 percent and at around 10,000 feet it may dip to 90 percent. Somewhere around 10,000 feet there is a big change and oxygen saturation can drop to 80 percent or below.

Acclimatizing to various altitudes can help improve these numbers up to a point. Know there is individual variability in the acclimation process and there is even variability among native dwellers at any altitude, beginning at birth.

Children born at various altitudes have similar oxygen saturations during the first 24 to 48 hours of life and the values change within the first four months of life. For example, newborns in Denver, Colorado (5,280 feet, considered moderate altitude) have saturation levels of 85 to 97 percent while those born in Leadville, Colorado (10,152 feet, considered high altitude) are 85 to 93 percent.

Though the time periods noted in a medical column weren’t exactly the same, it is interesting to note that after four months, the Leadville infants were between 89 and 93 percent saturation during wakefulness. Healthy, awake infants under the age of two measured between 90 and 99 percent in Denver. So there was some shifting up, particularly on the low end.

You can pick up a pulse oximeter at many local pharmacies. A common use for these devices includes measuring oxygen saturation in people with compromised lung function. Pilots and mountain climbers also use the devices to determine when supplemental oxygen might be necessary to avoid fainting.

I’ve been playing with an oximeter to look at oxygen saturation at my house (roughly 5,000 ft. measured on my Garmin) and Frisco, Colorado (roughly 9,100 ft.) I did this because much of my fun, training and racing is done at altitudes of 7,500 ft. or more and I was curious if my oxygen saturation changed much between the Front Range and the Colorado mountains.

The next blog will be more about what I’ve noticed in my experiment of one.

Heat acclimatization improves performance in cooler temperatures

guest — Thu, 02 Sep 2010 23:19:57 GMT

For the past couple of weeks I’ve been working on a two-part column series addressing acclimatizing to heat and humidity. You can find Part I at this link and Part II here.

The volume of information available on body temperature regulation, performance and all issues related is overwhelming. Boiling the information down into two columns was a challenge.

In my research review process, I found the information posted in the last blog, letting you know that there are gender differences in sweat rates.

Another interesting tidbit I wanted to share with you is from a University of Oregon research paper titled “Heat Acclimation Improves Exercise Performance”. The study was designed to examine the impact of heat acclimation on improving exercise performance in a cooler environment.

Twelve trained cyclists completed VO2max, time trial performance (I’m not sure of the time or distance) and lactate threshold tests in both a cool (13 C = 55 F) and hot (38 C = 100 F) environment both before and after a heat acclimatization program. Those results were compared to eight control subjects that completed the same tests before and after; but their exercise program (identical to the 12 subjects) was conducted in cool (13 C = 55 F) conditions.

You would likely expect the heat acclimatized group to improve in the hot conditions, compared to the control group – and they did. What you might not expect is that the heat acclimatized group improved performance in cool conditions after the heat acclimatization program.

While the control group had no changes in any of the test parameters in the second round of testing, the heat acclimatized group saw some impressive changes:

Time-trial performance by 6% in cool and by 8% in hot conditions.
Power output at lactate threshold by 5 % in cool and by 5 % in hot conditions.
Plasma volume increased (6.5 +/- 1.5%).
Maximal cardiac output in cool and hot conditions increased (9.1 +/- 3.4% and 4.5 +/- 4.6%, respectively).

Their conclusion was that heat acclimatization improves performance in temperate-cool conditions.

Interesting.

Blog Posts From Active Expert: Gale Bernhardt Tagged With acclimatization

Pulse Oximetry, Blood Oxygen Saturation and Altitude Acclimatization

Heat acclimatization improves performance in cooler temperatures