donkeydoug wrote:
Heat training works. Fake altitude training masks do not, and this has been known for years.
You can think of a mask as a rev limiter. They limit your bodies ability to do real work. So now you can't train in proper zones. But unlike altitude there are no physiological adaptions made to overcome this.
Remember:
Altitude- same volume, less oxygen
Breathing mask- less volume, same oxygen
The guy above who said his fitness improved by breathing through his nose might think he stumbled upon a hack to supercharge fitness, but in reality... He simply discovered the benefits of LSD running.
I’ve done nose breathing before too, like today I did 10 miles at 6:30s and my 5k PR is 15:58. That’s not LSD. My hr was high because I am coming off a break, but I tried this last summer, did most of my runs around 7 flat nose breathing and then one week in the fall I stopped and just mouth breathers. The result? I was running 6:30s at 140 bpm compared to 7:15 ish at 140 just days before and my tempo pace dropped from 5:30 to 5:20 or faster. It only lasted about a week and then my body lost the fitness though. Wish I timed it better with a race.