I think it depends on your density. If I exhale, I will sink. This is an item of curiosity to my wife, who has to work to stay underwater, even after exhaling

I think it depends on your density. If I exhale, I will sink. This is an item of curiosity to my wife, who has to work to stay underwater, even after exhaling completely. For more: http://www.quora.com/What-is-the-density-of-the-human-body http://www.quora.com/What-is-the-density-of-the-human-body