Course:EOSC311/2022/The Physiological Differences Between Athletes Living at Higher Altitudes Compared to Athletes Living Closer to Sea Level

Growing up watching hockey, there were several times where one team would be playing in Colorado and the commentators would mention that they have a home-ice advantage because of the higher altitude. This has always been noticed but I have never searched for the answer of why they mention that specific characteristic of Colorado. Throughout this Wiki page, the geological differences between Colorado, a high-altitude, mountainous area, and California, an area closer to sea-level with fewer mountain ranges, will be compared. The processes of how the Rocky Mountains formed and how the formation of this mountain range is unique are discussed. The physiological affects of living at higher altitudes will also be discussed, as well as why someone might want to train at different altitudes. This Wiki page attempts to provide insight on how living or training at different altitudes affects one's physiological and athletic ability, and how their athletic ability would be different if they trained/lived in an area closer to sea-level at a lower elevation.

Why did I choose this topic?

I chose this topic for my project because I am interested in why commentators mention that the Colorado Avalanche, a hockey team in the National Hockey League (NHL) have a home-ice advantage due to the high altitude. I always wondered if it actually affected the performance and how their bodies are affected by this difference in altitude. Does their training in Colorado affect their performance differently compared to if they trained in California?

Because I am studying in the faculty of Kinesiology towards my major in neuromechanical and physiological sciences, the possibility of physiological affects on an athlete due to the altitude and the geological characteristics of where the athlete lives is a topic of interest that involves both athletic and geological analysis.

Geological Differences: Colorado and California

Colorado

Colorado is a state located slightly west from the center of the United States of America, and is known for their rocky mountains and the higher altitude compared to the rest of the country. The elevation in the state of Colorado is the highest compared to the rest of states in the country, with the highest peak in Colorado being Mount Elbert, reaching about 4400 meters.

According to the United States Geological Survey, the mountains were uplifted during the Laramide orogeny around 80 million to 35 million years ago, and the glaciation and erosion of the rock and sediment caused the formation of the peaks and valleys of the Rocky Mountains to become what they are today. The Laramide orogeny, according to Brittanica, was a series of events producing mountains occurring in the western side of North America. Evidence shows that this mountain-producing event from the Late Cretaceous period (~65 million years ago) consisted of thrust faults, which are defined as breaks in the Earth's crust where older rocks are pushed above the younger rocks/sediments, and folds, which are permanent, wavelike deformations in layered rock/sediment. These geological processes were said to have occurred in the eastward direction, from the west coast inwards. According to Fanok, the mountains that were formed during the Laramide orogeny formed from the collision of the Pacific Plate and the North American Plate. The Pacific Plate subducted under the North American plate at a somewhat shallow angle, creating a subduction zone off the coast of California.

Mount Elbert, highest summit in the United States

A unique characteristic about the Rocky Mountains is the distance away from the subduction zone where they formed. According to Fanok, mountain chains tend to form between 320km to 650km inland from the subduction zone, but the Rocky Mountains formed much further inland at a distance of about 1000km from the subduction zone.

As you travel to higher altitudes, the partial pressure of oxygen decreases. The partial pressure is defined as the amount of molecules are in a given volume of air , and a lower partial pressure of oxygen means that there are fewer molecules of oxygen in the air as the altitude increases. While the partial pressure of oxygen at sea-level is 159mmHg, the partial pressure at Colorado Springs, which is a small town in Colorado about 1827m above sea level, is about 21% lower, meaning that there are fewer molecules of oxygen in the air . In terms of physical appearance, there is no evidence supporting that those who live at higher altitudes look different than those who live closer to sea-level.

California

Badwater Basin, lowest point in North America

California is a state in the United States of America that lies along the west coast of the country. Comparing the altitude between Los Angeles, a city in California, with Colorado Springs, a town in Colorado, Los Angeles has an altitude of around 93m above sea-level, while the altitude of Colorado Springs is about 1832m. Unlike Colorado, California does not have geological structures that rise as high as the Rocky Mountains, but California does have an area called the Death Valley, which contains the Badwater Basin, the lowest point in North America. Badwater Basin rests at 86 meters below sea level and the area is made up of salt flats covering almost 518 square kilometers. Although the Badwater Basin is already the lowest point in North America, it is said to still be sinking. Due to the uplift of the Black Mountains east of the basin, the valley floor (where the Death Valley is) is continuing to sink, and because of the low precipitation levels in that area, erosion of surrounding mountains is not able to fill the gap at a fast enough rate to keep up with the sinking.

Comparing the Badwater Basin and Death Valley with the Rocky Mountains, the area in California is much more flat and, as stated earlier, much closer to the sea level with some areas even dipping below sea level. With California being closer to sea level than being on the mountains, the concentration of oxygen in the Badwater Basin would be comparably higher in California compared to being in Colorado. The air closer to sea level is much more dense, allowing oxygen to pass easily from the air into the lungs, and with a higher concentration of oxygen, there is able to be a higher absorption of oxygen into the bloodstream.

Physiological Differences: how does the body change?

Being exposed to higher altitude, according to Ben Levine, can lead to an increase in ventilation as the body responds to the lower partial pressure of oxygen. How this can affect the body is that there will be less oxygen reaching the muscles, resulting in a significantly apparent limit in exercise performance.

According to Ezzati and colleagues, those who lived 1500 meters above sea level had a longer life expectancy than those who lived within 100 meters of sea level, with men living 1.2 to 3.6 years longer and women living 0.5 to 2.5 years longer. Ezzati and colleagues also concluded that living at a higher altitude could protect those from ischemic heart disease but also put those at a higher risk of chronic obstructive pulmonary diseases.

Hypoxia, which refers to a lack in oxygen, occurs often at high altitudes because of the decreased partial pressure of oxygen and the atmosphere being less dense leading to lower air pressure as well. As a person ascends to high elevations, their body will experience some initial affects from the lower concentration of oxygen. Their blood oxygen levels will begin to drop, causing hyperventilation, resulting in a decrease in carbon dioxide levels (respiratory alkalosis), as well as an increased heart rate, putting additional stress on the cardiovascular system.

High altitude sickness is also common for those who are not used to being at higher altitudes. Symptoms of high altitude sickness include loss in appetite, headache, dizziness, distorted vision, ringing in the ears, insomnia, nausea, and vomiting. These symptoms will improve as the person becomes more acclimated to the elevation, but more serious symptoms that may develop at higher altitudes include fluid accumulation in the lungs (high altitude pulmonary edema), or in the brain (high altitude cerebral edema), with both possibly being fatal.

As the person becomes used to the higher altitude and they stop experiencing any more of the symptoms of high altitude sickness, capillaries gain more muscle tissues, the lungs can increase in size, as well as the right ventricle of the heart, which supplies the lungs with blood. These effects of living and becoming acclimated to the higher altitude allows for the body to take in more oxygen as well as transport the oxygen more efficiently throughout the body. Acclimation can take several weeks, with higher altitudes taking longer, but with the adaptations, people living at higher altitudes may experience an increased level of personal fitness.

Athletic Performance: what differs between athletes?

Altitude training, according to Ben Levine, is usually done at 2133 meters (7000 feet) or higher. He also states that breathing the "thinner" air when living at higher altitudes over a long period of time can possibly enhance the athletic performance of athletes in competitions at lower altitudes. A major factor when training at high elevation is altitude-induced hypoxia, which refers to a decreased amount of oxygen being delivered to the muscles to burn the fuel and create energy needed to work. As the athlete adapts to the higher altitude from living and/or training there, they will have a larger number of red blood cells, which are the main carrier of oxygen to the muscles that are working. Having a greater number of red blood cells will allow the perceived rate of exertion of the athlete to gradually become lower as they will have their blood carrying more oxygen, assisting in fatigue and overall performance. When the athlete then competes at a lower altitude following their acclimation to the higher altitude environment, the additional oxygen available can possibly enhance performance by 1-2% for elite athletes. I believe that those who would benefit the most from training at a high altitude are those who participate in long distance, aerobic-focused sports. This is because with the training at increased elevation and the physiological adaptations that follow, aerobic fitness would increase the most. An increased lung capacity and improved efficiency in oxygen delivery to working muscles will allow the athletes to train and use the muscles for longer periods of time since the body mainly uses slower, more efficient forms of metabolism when moving at a lower intensity. Although I believe that there could be benefits for athletes who compete in sports that require a shorter peak performance and a higher, more explosive amount of power and strength, those who compete in aerobic sports such as long-distance running and cycling would gain the greatest benefits from training with "thinner air".

In team sports like hockey, I believe that yes, a team like the Colorado Avalanche may have a slight competitive advantage due to the higher altitude of their home arena. The main reason for this is because the opposing team may experience some sort of high altitude sickness or have a harder time adapting to the air since there is a lower partial pressure of oxygen. I do not think that training in the higher altitudes

Conclusion

In this article, the geological processes that caused the Rocky Mountains to form as well as the geological characteristics involving altitude were discussed. The differences in the oxygen concentration were discussed in relation to how it affects athletic ability and the physiology of athletes and non-athletes. The physiological effects of living and training at high altitude was also discussed, with the conclusion that those who train at higher altitudes will experience initial trouble with adapting to the altitude with the possibility of experiencing high altitude sickness, but over time, training at higher altitudes will benefit those who compete in long-distance, aerobic competitions most, compared to athletes who mainly compete in short-duration, high intensity, power, and strength competitions.

References

This Earth Science resource was created by Course:EOSC311.