Absolutely not. The opposite in fact. You want to fill your lungs and diaphragm with oxygen, and that cannot happen unless you relax your whole abdomen area, and breathe in low.
Begin to breathe in. Let it push your tummy out. Keep breathing and fill your lungs. You should be working from your diaphragm. This will provide a more solid, strong sound rather than a weak, airy one.
It's also good to maintain good posture while singing.
Hope this helps :)