Originally Posted by robedon
I try to exhale while swimming, and as I cross the pool I feel like I have no air in my lungs. .
Breathing is the most simple thing, except it is not. Yes, you could be in better shape, but not so bad that you can't complete 1 length, otherwise you wouldn't be doing triathlons.
Mastering relaxed breathing is the key to going from 10 yards to 10,000.
The more you can match your breathing to what you would be doing at a brisk walk in the open air, the better.
1) No tension in the neck shoulders and chest.
2) No forceful exhalation or inhalation. More effort than you would be doing standing still, but like I said, about what you do at a brisk walk. People who run are used to breathing harder, but it doesn't work at the slower breathing rate you are limited to while swimming.
3) Inhale when your arms aren't actively pulling -- you can't open your chest, while your back and chest muscles are working to close your chest.
If this is not working, "listen" more closely for excess tension.