any input on expanding lungs

A Tennessee Turn (I call them TNT's)will help. We did them and I suppose still do them at UT. Simply, underwater between walls and flags in a streamlined position, turn around underwater and press off the wall in a streamlined position passed the flags. I give my age groupers lengths of 200 - 400yds. High schoolers 300 - 600 yards. If it seems to be too easy, extend the length underwater. I also incorporate what I call "Gutbusters" 5 x 200 with 1min RI. At the beginning and after every even wall, push off the wall and swim as far as you can underwater, not more than 25 yards. Once in a while when we are resting. 1-2-2-1's. Another UTer. 5 x 100 at 2:00, 1 breath the 1st 25, 2 breaths the 2nd, 2-3rd, 1-4th. Decrease interval for better result. "666" is another one but I have run out of time. Let's just say it's very evil. These help my swimmers learn breath control and I feel increases capacity to hold air.

A Tennessee Turn (I call them TNT's)will help. We did them and I suppose still do them at UT. Simply, underwater between walls and flags in a streamlined position, turn around underwater and press off the wall in a streamlined position passed the flags. I give my age groupers lengths of 200 - 400yds. High schoolers 300 - 600 yards. If it seems to be too easy, extend the length underwater. I also incorporate what I call "Gutbusters" 5 x 200 with 1min RI. At the beginning and after every even wall, push off the wall and swim as far as you can underwater, not more than 25 yards. Once in a while when we are resting. 1-2-2-1's. Another UTer. 5 x 100 at 2:00, 1 breath the 1st 25, 2 breaths the 2nd, 2-3rd, 1-4th. Decrease interval for better result. "666" is another one but I have run out of time. Let's just say it's very evil. These help my swimmers learn breath control and I feel increases capacity to hold air.