"Most altitude training camps continue at least 2-3 weeks at moderate (6,000-8,000 feet) altitude in order for the advantages to be fully recognized after returning to sea level."
So at 8,000 feet, you'll experience less oxygenation of your blood and other tissues. To compensate, you need to breathe more often. Altitude training is used by athletes who want to improve their performance at high levels by testing themselves at different times during the year in conditions similar to those they will face when the actual event takes place.
Altitude training can also be useful if you want to lose weight because you need to breathe more air per kilo of body weight at high altitudes than at low ones. Thus, you burn more calories even while sitting on the couch!
Finally, altitude training can help you recover faster after a hard race or workout. The reduced amount of oxygen in the air helps your body rid itself of the toxic substances produced as a result of all that activity.
In conclusion, altitude training lasts for about three weeks at moderate altitudes and can benefit many sports including running, cycling, and soccer.
Most coaches advise at least two weeks at altitude, although this isn't an all-or-nothing proposition: Even if you just have a week, mountain training can provide physical and mental advantages that will continue for several weeks after you return to sea level.
The primary benefit is reduced oxygen consumption while exercising at high levels above sea level. Because more oxygen is available to your muscles when you exercise at high altitudes, you require fewer deep breaths while working out at these locations. This leads to less fatigue during workouts that involve intense breathing exercises (such as weight lifting or sprinting).
The secondary benefit is reduced perceived exertion during exercise at high elevations. When you work out at higher elevations, you feel less tired even though you're doing more work. This advantage disappears when you return to lower elevations.
The third benefit is improved blood flow due to decreased heart rate while exercising at high elevations. Heart disease is the number one cause of death in the United States, so anything that improves blood flow to the heart is beneficial.
Finally, high-altitude training has been shown to improve lung function. This may be particularly important for people who struggle with asthma or other respiratory conditions.
All in all, high-altitude training provides many benefits that last for several weeks after you return to normal levels of activity.
Scientists normally advocate remaining at altitude for at least three to four weeks to see consistent hemoglobin improvements, but the research authors note out that in the actual world of elite athletics, middle-distance runners sometimes travel to altitude during the track season for a two-week "top-up" camp. Such camps are usually held in the spring or fall, which is about as far from the heart of summer as one can get and still be considered high in the mountains.
The scientists write that eight days at altitude was enough to improve hemoglobin levels in moderately anemic athletes but notes that more time at higher levels will further boost them. They conclude that traveling to altitude for two weeks would likely bring about even more beneficial effects than their study showed.
To put it simply, the longer you stay at high altitude, the better it is for your health. The researchers recommend staying for at least three weeks but say that going for eight days is enough to see significant changes in blood chemistry markers associated with increased oxygen carrying capacity.
Altitude training is used by many athletes as part of a pre-competition preparation program. Middle-distance runners especially like to travel to higher locations and stay for a few weeks at a time if they can afford it. This allows them to gain a competitive advantage by running faster times while their bodies are still in balance, rather than after they return to sea level where they often feel fatigued or sick.