The pros and cons of altitude training.

long-distance track runners, and in particular marathon runners. This involves exposure to high altitudes for several days, weeks, or months, undertaken

with the intention of improving their competitive performance at lower elevations. Itis very much a controversial regimen, and there is a huge number of opinions, medical facts, and statistics both for and against undertaking this type of training.

[is benefit of altitude training is currently a hot topic in the world of athletes,

Potential Positive Effects

¢ Invigoration—the “feel-good” factor

¢ Increased oxygen flow throughout the body ¢ Enhanced muscle response

¢ Enhanced results during training sessions

Potential Negative Effects

¢ Risk of altitude sickness

° Lethargy

¢ Muscle wastage (as with overtraining, can be during or after)

¢ No noticeable improvement in performance at lower altitudes

Mount Kilimanjaro as a training ground

If the intention is to compete at altitudes well above sea level, altitude exposure could be beneficial to a marathon runner. For example, a trek up Kilimanjaro could be beneficial in terms of endurance and stamina and learning the importance of pacing.

It would also offer an excellent opportunity to experience a whole sequence of varying temperatures and climates and the effect of increasing altitude on the body.

An athlete who has only ever trained at sea level, no matter how fit, would need to put into place the same techniques for acclimatization as any other Kilimanjaro challenger before attempting it. Surprisingly, some of the fittest athletes can find that they are prone to the worst effects of high altitude.

Acclimatization

Many athletes attempting to enhance their performance by travelling to and training at high altitudes neglect to understand the essential need for acclimatization.

There are definitely precautions that need to be taken when embarking on a stint of training at an altitude of the level where physiological changes to the way the body functions naturally take place.

Acclimatization is far more complex than many realize. Men especially should be aware that they are more susceptible than their female counterparts to the natural effects. To be fair, it sometimes does not help that they tend to compete and to show off.

Sometimes it is the really obvious solutions to aid acclimatization that are ignored. For example, rather than flying straight to a high-altitude area, traveling steadily upward to the destination by alternative transport can save time requiring rest with no training.

For those who have little or no alternative to flying direct, resting on arrival is crucial. Providing a period of time without any strenuous exercise will give the body sufficient time to adjust. This will vary from person to person and will be between 12 and 48 hours.

Before traveling for a high-altitude training session, having a plan of gradually increasing activity and working up to the normal (full) training program is a sensible idea. In addition, it is a must to drink more fluid than usual and to eat much more calorific food (ideally carbohydrate based) than would normally be the case.

Taking part in specifically designed acclimatization treks is highly recommended. These are planned routes that will take account of scientific evidence concerning “safe” ascents.

In a nutshell, ascending up to 3,000 meters should not cause any problems at all. Thereafter, a maximum height ascent of 500 meters should be adhered to. In certain situations, where this has been exceeded, a partial descent to camp for the night is insisted upon.

Altitude-exposure techniques

Training at high altitudes is usually undertaken by athletes for the sole purpose of enhancing their performance at lower elevations. Being at high altitude stimulates the red blood cells, which enhances their efficiency in transporting oxygen to the muscles.

In turn, hemoglobin increases, blood-vessel density increases around muscles, and the lungs are able to take in more oxygen. To an athlete, all of these factors equal less muscle fatigue, an essential factor for endurance sports and especially for marathon runners.

There is a downside to this—the fact that the hypoxia resulting from training at altitude can cause a level of muscle wastage. In some instances this can cancel out the benefits.

There are three recognized altitude-exposure techniques widely used amongst high-class athletes:

° Live high, train high ° Live high, train low ° Live low, train high High = 6,500 to 8,000 feet above sea level. Low = Sea level to 4,000 feet above sea level

Live high, train high This method is intended to provide maximum high-altitude exposure. Whether this is of benefit in competition at lower levels of altitude still remains an extremely controversial subject amongst athletes and scientists alike.

Ultimately, it may well come down to individuals and how well their bodies cope with functioning at high altitude rather than being beneficial to any or all athletes.

Live high, train low This is currently the most extensively recommended method. The theory is that normal living is done at high altitude to enhance the positive effects of the lower oxygen, whilst specific training is carried out at a low enough level to make full use of those benefits.

This would usually amount to a minimum of 12 hours per day being spent at high altitude for a period lasting at least three weeks but ideally four to six weeks. This particular method has been far more extensively used and monitored than the other two; it therefore appears that there are more positive reports about its benefits.

Live low, train high

This method involves the reverse of the one above—that is, training at height but descending for the remainder of the time. It is the least popular of the three and therefore has the least scientific evidence to show that it is more than moderately beneficial to athletes.

A technological alternative

Relatively new to the market are the various systems available that claim to replicate altitude exposure. They are intended to be used during normal training at sea level, or even whilst asleep. At the present time there is not a substantial enough amount of research available to determine whether they are adequate substitutes for the “real thing.”

They do appear to be receiving some interesting testimonials from people who have used them prior to climbing Mount Kilimanjaro, but it could well be that they were individuals less prone to the inevitable effects of altitude.

The negative physiological effects of high altitude

To an athlete, the notable benefits of high altitude may outweigh the negative effects and the danger of becoming seriously ill. But it cannot be stressed enough that altitude sickness is not confined to unfit people!

There are changes to the body that are expected to take place naturally at higher altitudes, which are not particularly pleasant but do not necessarily indicate the onset of altitude sickness:

¢ Breathing more rapidly/getting out of breath more quickly

¢ Sleep apnea (breathing stops for short periods)

¢ Sleeping fitfully and/or waking up frequently

¢ Increased urination

Altitude sickness There are three recognised forms of altitude sickness, each with increasing levels of severity:

« AMS (Acute Mountain Sickness)

¢ HAPE (High Altitude Pulmonary Edema)

¢ HACE (High Altitude Coronary Edema)

There is no definitive altitude that can trigger altitude sickness. Some people will be affected at relatively low altitudes, whilst others experience no problems at all at any height.

Apart from the fact that there are more recorded male cases than female, age, height, weight, and level of fitness have no direct bearing on the effects of altitude.

AMS AMS is very common amongst climbers and can occur at any time, depending on the individual.

Symptoms:

¢ Nausea or actual vomiting

¢ Mild to severe headache (not helped by nonprescription medications)

¢ Tiredness but inability to sleep

¢ Dizziness or a feeling of lightheadedness

¢ Lack of appetite

¢ General fatigue and apathy

Treatment: If the symptoms are recognized and acknowledged, rest and partial descent are usually sufficient to allow ascent to continue at a later stage.

This is triggered by a lack of oxygen that causes blood vessels in the lungs to tighten, thereby creating excessive pressure within the lung arteries and a resulting leakage of fluid into the lungs themselves. Symptoms: ¢ Tight chest/difficulty in taking a full breath (even at rest) ° Purple tinge to the lips and fingernails ¢ Raised temperature ¢ Rasping when breathing ° Extreme feeling of fatigue ° Cough that produces blood-tinged froth Treatment: Asthma medication plus steroids, usually dexamethasone (a corticosteroid), are used to offset the symptoms, and descent at the earliest opportunity is essential. HACE This can develop from the initial AMS if it is ignored. It may commence without symptoms or even whilst sleeping. It is a very serious condition, caused by a fluid buildup around the brain, but this can go unnoticed by the sufferer due to lack of oxygen affecting the thought processes. Symptoms: ¢ “Drunken” appearance—staggering, unable to walk straight ¢ Inability to coordinate ¢ Changes to normal behaviour and thinking ° Very severe headache and vomiting ¢ Hallucinating ¢ Complete exhaustion/inability to move * Coma

Treatment: Emergency medication, usually dexamethasone (a corticosteroid drug), is used to control the swelling and reduce fluid buildup. Rapid descent should begin at the earliest opportunity.

In addition, HARH (High Altitude Retinal Hemorrhage) can develop, usually secondary to HACE or HAPE rather than as a solitary problem. As such, it is rarely mentioned in information about altitude sickness.

Symptoms: ¢ Blurred vision ¢ Bleeding from the eyes

Treatment: Little is known about HARH as it is a relatively rare occurrence. It seems that most cases resolve without the need for medical intervention once the sufferer has returned to lower altitudes.

Because HARH is usually associated with severe HACE, in longer-lasting cases, steroids and diuretics may be used under medical supervision to treat both problems simultaneously.

Some specific scientific facts

Atmospheric or “barometric” (measured by a barometer) pressure is defined in terms of millimeters of mercury and is often described as “the weight of the air.”

What that actually means is the force exerted by the atmosphere at a specific point. At sea level the atmospheric pressure is approximately 760 mmHg; by 12,000 feet it has dropped to 480 mmHg.

The percentage of air in the atmosphere always remains similar, at around 21 percent regardless, but the number of available oxygen molecules per breath reduces at higher altitudes. For example, at 12,000 feet the reduction is 40 percent.

Additionally, this reduction in oxygen intake causes leakage of fluids from the capillaries into the brain and lungs. Without sufficient, steady acclimatization, the end result can be the severe altitude sicknesses HACE or HAPE.

How to avoid altitude sickness

Altitude sickness can occur at relatively low altitudes (8,000 feet), and acclimatization is the key to preventing it. It is easy to make the mistake of trying to do too much, too quickly, especially as an active, fit person.

The biggest problems arise with isolated climbs, like Kilimanjaro, because it is one big ascent. This can be offset to some degree by spending time in areas where both ascending and descending are required, as would be the case traversing a range of mountains.

All climbs should be attempted steadily right from the start, especially those that will end in an ascent in excess of 10,000 feet above sea level. Toward the end of the climb, no more than 500 feet of height should be gained in any one day to offset altitude sickness.

Under no circumstances should alcohol, tranquilizers, or sleeping tablets be used. They can either mask symptoms of altitude sickness or increase them. The same goes for smoking. Plenty of good-quality calorific food and as much fresh water as can be consumed are the best preventatives.

Having a climbing partner is a very good idea. The partners can provide each other with moral support and be watchful for signs of altitude sickness, which could ultimately save a life.

Preventive medication

This is a much-discussed subject. Some recommend using acetazolamide both before and during ascent as a preventive medication. This drug is a diuretic and as such inhibits the buildup of fluid that takes place when altitude sickness becomes apparent.

Others suggest that it should not be taken unless there are symptoms because more serious problems could be masked by the medication itself. A final school of thought suggests that it should be taken only during a partial descent if specific symptoms have been identified.

Medication as a treatment

The most prescribed medication for altitude sickness is the steroid dexamethasone. This is used only as an emergency treatment for serious cases of altitude sickness, such as HACE. It works by inhibiting the overproduction of corticosteroids that cause the symptoms and thus reducing fluids and swelling around the brain.

It is not safe to use as a preventive medication because it is more likely to mask symptoms of altitude sickness rather than prevent them. It should be kept for medical emergencies only, especially those that arise overnight when immediate descent may not be possible.

Nifedipine and sildenafil (Viagra) are sometimes used, as both are drugs that assist with opening up the blood vessels in the walls of the lungs, thus reducing the high pressure in those vessels that is forcing fluid into the lungs themselves. Both can be a useful emergency treatment for HAPE.

External treatments

In an emergency case of severe altitude sickness, either HACE or HAPE, rapid and immediate descent is essential. In particularly bad cases where the sufferer has slipped into a coma, pure oxygen may be administered and it may be necessary to physically carry the victim during the inevitable descent.

Side effects

All medications prescribed for the treatment of altitude sickness can have side effects, but there is very little documentation about who may be affected and in what way. It is always best to consult a doctor in advance of travel, especially for anyone already taking other prescribed medication.

The golden rules

There could be inexhaustible lists of dos and don’ts, but there are just three golden rules where altitude is concerned:

1. “If you feel unwell, you have altitude sickness until proven otherwise.” 2. “Do not ascend farther if you have symptoms of altitude sickness.” 3. “If you are getting worse, then descend immediately.”

[Direct quotations courtesy of Dr. David Schlim.]

Summary

The benefits of training at high altitude and using somewhere like Mount Kilimanjaro as a training ground are somewhat debatable. Whilst some athletes are convinced that training at high altitudes enhances their performance, there are an equal number of scientific reports that suggest this cannot be the case. Knowing in advance the effects of simply being at high altitude versus the symptoms of altitude sickness itself is essential to personal health and safety. Every year, many people die from altitude sickness, and it is not something to be taken lightly. The more reading and research that can be carried out before

considering this particular form of training, the better. &