Tightness & eventual nausea when breathing vertically at surface

[Neilwood]

@2018diver I had a similar feeling on my OW course wearing a jacket type BCD (which had to be snugged tight to stop it sliding up when inflated) very tight chest and struggling to breathe properly. I had the choice of full inflation or full breath but definitely not both.

Made it through the OW and bought myself a BP&W where the harness is not affected by the inflation of the bladder (note any back inflate will have the same effect as the bladder is behind you). Never had any issues since.

Any comments about back inflate tipping you forward are more to do with placement of weight than the BCD itself. Put the air behind you and the weight in front and you will tip forward. Spread the weight around with more at your back or on the cam bands and it isn't really an issue. Also when on the surface with a harness with a crotch strap it is actually pretty comfortable sitting on the crotch strap.

 

[Lobzilla]

I'm currently in my OW certification class and have noticed something strange. When I am geared up, in a wetsuit, and floating or standing vertically in the pool, with water up to my chest/neck, I feel an uncomfortable tightness in my chest with breathing. After long enough, it progresses to mild nausea.

If I am horizontal, the feeling goes away. I have no problem when I'm underwater with the regulator swimming around, or floating on my stomach breathing through a snorkel, or floating on my back breathing air. It seems to be only when I'm vertical.

I don't have this problem when I'm just wearing swim trunks in a pool with no scuba gear. My theory is that the restrictiveness of the wetsuit, combined with the pressure differential of my submerged lungs and my head out of the water, are making it uncomfortable to breathe in this position. But it concerns me that it feels so uncomfortable and eventually leads to nausea. It makes me worry about my upcoming checkout dives where there will certainly be lots of time floating vertically at the surface while other students demonstrate their skills.

I am not otherwise prone to nausea and never get carsick or seasick. I'm a moderately active 35 year old male, not overweight.

Has anyone else experienced this?

When we are upright in the water, there is more pressure on our lungs than on our mouth or regulator. There might be additional pressure on our chest from a tight fitting suit. So we have to suck the air down against that pressure, which is something our lungs were never designed for or evolved to.

The solution is here, in your own words: "If I am horizontal, the feeling goes away." So, dive horizontally where the regulator and your lungs are on the same pressure level.

On the surface, just lay on your back or flat forward with regulator or snorkel in your mouth.

For surface swims in the ocean, I prefer frog kicking while laying on my back and breathing past my regulator mouthpiece. I also do an occasional roll to check where I am going.