If I train with a mask that restricts airflow, it will simulate training at altitude.FICTION
As stated before, the benefits of altitude training are not found from areas that lack oxygen, but from areas of lower-barometric pressure. Restricting airflow does not simulate training in altitude. In fact, training with reduced oxygen can cause serious problems like hyperventilation, disorientation, rapid heartbeat, elevated blood pressure and loss of consciousness.
Better use of altitude training would be sleeping in a hyperbaric tent. These tents create an enclosed, simulated altitude that allows the body to see results of altitude training while residing at sea level. These tents can be purchased or rented and assembled in your own bed. Some places offer hyperbaric chambers that you can visit for a fee. The "altitude" is adjusted slowly as the body adapts, and it has been proven to yield positive results.
Though air-restrictive masks may prove beneficial for some athletes whose sport requires working with low-oxygen levels, the masks pose danger to those using them to "get fit."
If I train at altitude, then race at sea level, I'll see better performance.FACT
Well, this is a tricky one. Depending on the environment, it could backfire on you. If you spend time training in Colorado, which is high and very dry, then do a marathon in Florida, which is low and very wet; you may experience some problems because of the humidity. However, generally, you should see better times, strength and recovery if you train at altitude (or simulated altitude), and then perform at sea level.
If I train at sea level and plan to do a race in the mountains, then it's probably a good idea to get there a few days early to prepare for the race.FICTION
When you're not accustomed to altitude, you have two choices: do the race immediately—within a day—or wait 7 to 10 days before racing. If you get to an event a couple of days before, your body has time to figure out that you are in a different environment, and then it will start making the necessary changes it needs to survive at altitude. Your body will become stressed, and then it will show in your performance.
If you do the event immediately, it will not have time to start adapting, and you should not see terrible challenges to your pulmonary system. If you get there 10 days ahead of time, your body will have plenty of time to fully acclimate.
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