any input on expanding lungs

Bill-- Thanks for the excellent explication here. Two sideline notes: 1) I took my son to U. Michigan a couple years ago. In 1970, I was the second worst person on the Michigan swim team, and I wanted to show my son the pool where I vomited during practice. It had been covered over and turned into a volleyball court! A metaphor, I suppose, for what has happened to me... In any event, we found the new natatorium where Bob Bowman was coaching two distance swimmers. I introduced myself to the coach, who was exceptionally nice (he ended up giving Ben and me a bunch of swag--t-shirts and the like.) Anyhow, I noticed that the two swimmers were wearing swim snorkels and repeating 100 m swims on a ridiculously short interview. I asked the coach if the swim snorkels were being used to help balance/smooth out their strokes. He said not really. Instead, there were diaphram-like membranes in the mouthpiece with a very small hole cut in it. The swimmers had to really struggle to extract air through this hole. I couldn't believe how fast they were going, a feat made all the more spectacular when I learned they were straining to breathe through pinprick sized holes! Evidently this was a way to train some aspect of their air-processing physiology, though I am not sure exactly what. 2) A magazine I write for is trying to arrange for me to get one of those hypoxic bed-tents that allow you to sleep at altitude and then workout at a normal air-rich environment. In recent years, it seems, the idea that you should train at high altitude has been discredited because you just can't do enough hard work to get in optimal shape. The concept now is to sleep at altitude, to basically "blood dope" naturally, but then work out where you get enough air to really train hard. Not sure if this will do anything for me except trigger a massive infarction, but I will keep you posted if the tent actually arrives!

Bill-- Thanks for the excellent explication here. Two sideline notes: 1) I took my son to U. Michigan a couple years ago. In 1970, I was the second worst person on the Michigan swim team, and I wanted to show my son the pool where I vomited during practice. It had been covered over and turned into a volleyball court! A metaphor, I suppose, for what has happened to me... In any event, we found the new natatorium where Bob Bowman was coaching two distance swimmers. I introduced myself to the coach, who was exceptionally nice (he ended up giving Ben and me a bunch of swag--t-shirts and the like.) Anyhow, I noticed that the two swimmers were wearing swim snorkels and repeating 100 m swims on a ridiculously short interview. I asked the coach if the swim snorkels were being used to help balance/smooth out their strokes. He said not really. Instead, there were diaphram-like membranes in the mouthpiece with a very small hole cut in it. The swimmers had to really struggle to extract air through this hole. I couldn't believe how fast they were going, a feat made all the more spectacular when I learned they were straining to breathe through pinprick sized holes! Evidently this was a way to train some aspect of their air-processing physiology, though I am not sure exactly what. 2) A magazine I write for is trying to arrange for me to get one of those hypoxic bed-tents that allow you to sleep at altitude and then workout at a normal air-rich environment. In recent years, it seems, the idea that you should train at high altitude has been discredited because you just can't do enough hard work to get in optimal shape. The concept now is to sleep at altitude, to basically "blood dope" naturally, but then work out where you get enough air to really train hard. Not sure if this will do anything for me except trigger a massive infarction, but I will keep you posted if the tent actually arrives!