Take a few deep breaths before, then on the last one suck in oxygen as much as you can. Also, when you're underwater don't move at all, it saves energy.
If this is meant to be a serious question i guess its a funny-serious question
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in terms of smoking helping you hold your breath longer
No, it does not help you hold your breath...
A roach can. Roaches can hold their breath for 40 minutes, while the longest a human can go it u to about ten minutes. On average people hold their breath for about a minute, but free swimmers go for...
it depends, if the carotid artery and/or jugular are cut then you cant do anything about it, your virtually dead. if your windpipe, esophagus is cut then it depends, you want to keep as much blood...