Running out of gas....

3URXX,

I experience the same thing when I "forget" to exhale as forcefully as I should.  Like you, doing open turns eliminates the issue.

It is important to remember that the time it takes to do a flip turn is likely equivalent to 4-6 strokes without a breath.  I count the turn itself as two strokes and a nice long push-off (past the flags) as another 2.  If you are holding your breathe for 2 strokes into a turn and for 1-2 strokes after surfacing, you are going a long time without breathing.  That pushes the CO2 levels pretty high creating the awful feeling you experience.

As Kyle mentioned and I have found at our age, open turns might not be all that slower than flip turns - especially if we can swim harder between the walls.

good Luck!

Thanks Windrath.  I started doing a set of 50's, 25 free down, no breath on last two strokes, flip turning into a breaststroke pull out.  Seems to help some.  Thanks for the reply

Thanks Windrath.  I started doing a set of 50's, 25 free down, no breath on last two strokes, flip turning into a breaststroke pull out.  Seems to help some.  Thanks for the reply

Problem solved.  As a youthful swimmer, I was taught to take two strokes after each flip turn prior to breathing.  While it is hard to get used to, I now take an immediate breath after the turn (usually at the flags) and presto, gassing out reduced tremendously.