Swim test

[Lead_carrier]

Plus, holding your breath on scuba is only bad if you close the glotis *and* are ascending. That nonsense they teach you in OW 101 leads people to believe that holding their breath will lead to an instant embolism rather than explaining the real physiology behind it.

To a large part Soggy, this is true. Unfortunately, most of the explainations that I've gotten for a lot of my questions are so much bull that I don't see why people still try using that explaination. And this is with all agencies not just one or the other.

 

[Frank O]

What is the point of the breath hold swim. IMHO, it does not seem like a good idea to even start a muscle memory of moving underwater while holding your breath while on SCUBA.

The breath-hold swim test isn't done in full scuba gear. As someone who has spent several years doing both tank-dives and freedives, I can vouch that I haven't developed a muscle memory making me hold my breath during scuba ascents.

 

[H2Andy]

well... if danger of developing muscle memory re/ holding your breath is an issue,
i guess we better never hold our breaths, ever, for fear of starting down that
slippery slope.

(Oh god the cat litter stinks... but i WILL DIE UNDERWATER if i hold my breath now!!!
Must.... not...stop...breathing...)

 

[Diver0001]

The breath-hold swim test isn't done in full scuba gear. As someone who has spent several years doing both tank-dives and freedives, I can vouch that I haven't developed a muscle memory making me hold my breath during scuba ascents.

It's one of the confined water skills for the IANTD advanced nitrox course. 50ft breathhold swim in full scuba commencing air sharing at the end and then removing your mask and swimming for another 250ft maskless on your buddy's alternate.

R..

 

[spectrum]

It's one of the confined water skills for the IANTD advanced nitrox course. 50ft breathhold swim in full scuba commencing air sharing at the end and then removing your mask and swimming for another 250ft maskless on your buddy's alternate.

R..

Do you get a good last breath?

Pete

 

[JustinW]

I don't say this to be cocky, but having taken physics in high school, I found the dive physics and physiology incredibly simple and the tables a simple 3 step process. I understand that *some* people just won't get it (and I spent 3 1/2 of the 4 hours of my Nitrox class sitting around while the instructor explained how to do air tables to the other student), but there is certainly room for an attempt to explain the hows and whys behind the skills. Besides, going from explaining Boyle's law and expansion injuries to explaining that expansion injuries only can occur when you are ascending to explaining that there are ways of "holding" your breath that don't close close off the windpipe doesn't seem like too much of a stretch.

Diving is both an intellectual and physical activity and we need to get away from this lowest-common-denominator thinking.

Thats great for you, but do you see the potential danger in it with an OW test. Different situations are different as far as a teaching atmosphere and who the students are. Imagine, as an instructor, telling students to not hold their breath, but then saying that you can do it if you do it a certain way. An Instructor is responsible for their students for up to 5 years after certification. In OW curriculum, that is not a skill that is required to be taught. Telling the students about it and not showing it is extremely dangerous, as the chances of a student trying on their own or not completely understanding could cause death. Again, I can understand teaching these things in a continuing education, but not at the most basic levels of education to get into the sport.

 

[H2Andy]

Again, I can understand teaching these things in a continuing education, but not at the most basic levels of education to get into the sport.

i guess my question is, are we doing the students a service by teaching this way?

maybe the answer is that the teaching format needs to be changed so that these
topics can be covered in more than cursory depth.

 

[freediver]

An Instructor is responsible for their students for up to 5 years after certification.

?Curious where you got this information? Is the student filed away after the 5 year period?

 

[Sideband]

Plus, holding your breath on scuba is only bad if you close the glotis *and* are ascending. That nonsense they teach you in OW 101 leads people to believe that holding their breath will lead to an instant embolism rather than explaining the real physiology behind it.

Part of the trouble is, you can't tell if someones glotis is open without seeing bubbles unless you shove your dive light down their throat to look for yourself. As new students they need a set rule. What they don't need is a rule that has an exception, if done properly. The very simple, "If you are not inhaling then you should be exhaling." is also very effective and safe.
Also, regarding, "*and* are ascending": A new diver is not going to hold their breath with empty lungs. Most likely their lungs are going to be filled to capacity and they will start to ascend and not even notice because they are thinking about all of the other stuff they are learning and are nowhere close to having perfect buoyancy control. Heck, in my limited experience I've seen someone panic thinking their reg was not giving them enough air. The real problem was they weren't exhaling (or at least not enough). If it's possible for someone to not realize that then there is no way they are going to be aware of the state of their glotis.
Some concepts are better left for later in the learning process and IMO this is one of them.

Joe

 

[JustinW]

Sideband, I couldn't have said it better myself. Exclusions to a rule are not what new divers need. It isn't necessary and that information will not help them learn to dive. New divers have enough to learn with the basics, adding complicated rules and exceptions will not help them master the basics.