The only three ways to not float up when swimming underwater.

1. Blow out all the air in your lungs, that way you will sink, but not be able to hold your breath very long

2. Use a weight belt, a weight belt will help you sink, but be careful to not put on more weight than what you are able to float with on the surface. And remember that you have to bring all this weight up again.

3. Swim deeper. If you swim deeper the air in your lungs will be compressed and you will be less buoyant in the water. Swim deep enough and you will not float anymore

Davide Dameno on Youtube:
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Music in the video:
Neonpigeon by Ambient Light
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