No mask, no reg swim

[JCM@Atlam]

I would think you should use a flutter kick - to get there.
I would practice snorkeling with the jet fins and try to do several fast 50 yard swims in the pool. this should improve your technique and will result in strengthening eventually. Breathing from the snorkel.

Then (on the same day) I would practice the breathhold stuff - with a partner. First let yourself calm down and relax after the 50's. Then wear a weight belt and just do some static breathholds on the bottom with no mask. You should be able to do 45 seconds or so without trying. maybe 3-4 with a good 2 minute rest between. Don't push it, just see what you can do with only very slight uncomfortableness.

Then with a mask and snorkel and the fins, just do some casual surface swims with a relaxed flutter kick and no breathing. Try to swim gently and just see how far you get. 25 yards really should not be that hard. Again, don't push hard, just see how far you can get with maybe 80% effort. After you master 25 yards several times, you will feel better. It is not hard.

Do that work out 2-3 times in a week and you should be in better shape and way more confident and relaxed.

I would not believe anyone who tells you that you have another 2 minutes of apnea before you pass out (after you feel urgent need to breathe). If you feel bad come up! Don't hyperventilate, but taking 2-3 deep inhalations and exhalations before the dive should help.

A good bit of the apnea performance is psychological and the feedback you get from your body. If you have not adapted to the stress of breathhold, you will get panicky, you will flex muscles that should be relaxed, your brain will race and burn more oxygen (DO NOT discount this effect). You really want your breathhold (apnea) to be, for the most part a comfortable and relaxed activity - not something super stressful and difficult like lifting a heavy weight in the gym. You want to be saying to yourself (internal dialog).. I feel fine, I'm good, I'm relaxed, I'm moving gracefully and efficiently. NOT "I think I'm going to die!"

If you have normal physiology, your battle is within your brain and also making sure your kick is efficient and reasonably powerful and 15 meters should be very attainable.

I've been practicing around the house. I've found that the few deep breaths beforehand make a world of difference. I can now manage 90 seconds sat down which feels like a reasonable effort.

 

[JCM@Atlam]

i remember when i was working towards my instructor level and i had to practice my swim (we are talking about a horizontal swim and not an emergency ascent correct?)
i think i had to do 15 meters.
i found it made a big difference which fins i used. at the time a had a pair of apollo split fins and found they worked the best for me.
but we did it without gear on.
going full out is def not the way to approach it. i agree with the others that being as relaxed as possible is key. it is surprising how much energy your body will burn when your muscles are all tense.
obviously being as streamlined as possible will make a big difference as well.
i would assume you should be able to do 15 meters in 30 secs?
i am quite confident there is no way i could swim that far with all my gear on in one breath. not these days thats for sure.

Yes, horizontal with 2x AL80. I am glad I asked the question on here, the replies have been very helpful. I have realised that several deep breaths beforehand really delays the urge to breathe. I think Jetfins are more suited to moving a greater mass (me 83kg + the two cylinders and 5kg of lead)

 

[John C. Ratliff]

I'm doing IANTD Advanced Nitrox (in sidemount). Today I had to do a no mask, no reg swim for 15m. I failed and didn't even make it halfway without reaching for my regulator, at which point I realised I'd dropped my mask and nearly panicked. Not great My question is, how long should this swim take? I can hold my breath for 60 secs sat on the sofa but I can't see me ever holding my breath for more than 30 secs in this scenario. Any tips on successfully completing this exercise would be appreciated.

JCM,

Sometimes divers go into diving not really understanding about breathing. This diagram from the U.S. Navy Diving Manual of 1970 shows lung volumes, and how we talk about them. Most people who get into diving now are not former competitive swimmers, and so don't understand that they have a much greater volume of air available than they usually use. Modern regulators are so easy breathing that people don't change their breathing style when diving now (beginners especially). So they only use that 0.5 or so liter tidal volume. But if we take a very deep breath, we can use some of that inspiratory and expiratory reserve volume in breathing. Competitive swimmers, who must learn to swim with their mouths underwater sometimes, typically know instinctively to breathe deeply. Most others don't learn this until it is needed.

For my breathing, I typically breath deeply, but less rapidly, than many people. I have tested my ability to cope with a sudden out-of-air situation, and from a 16 foot deep pool exhaled, after shutting off the air to my tank. I could still swim horizontally over 60 feet to a surface, exhaling some as I went. Tthat's because there is still a lot of air in my lungs.

The same is true for you. Even with an exhalation while breathing in the tidal volume, you have a liter of air available for swimming. But with a full inhalation, you hove 3-4 liters of air available for swimming your 45 feet horizontally. You just need the confidence that you can do it.

The other thing is not to use the "frog kick" when doing this test. Use a normal "flutter" kick, to get maximum efficiency from your fins. The frog kick is not an efficient kick, and should be abandoned if you need to really get to a destination underwater. The frog kick is used by cave and shipwreck divers, not to move efficiently, but rather to not stir up sediment and reduce visibility. So keep that in mind.

SeaRat

 

[johndiver999]

I've been practicing around the house. I've found that the few deep breaths beforehand make a world of difference. I can now manage 90 seconds sat down which feels like a reasonable effort.

That is pretty good. I hate practicing static breathhold, so I pretty much never do it. However, a better dry practice is to walk and count steps. I can (usually) do 25 strides (counting each left leg extension) during a casual walk. Learning to do breathold when doing an activity is more relevant (or similar) than laying on a couch.

A few deep cycles helps to remove CO2 and makes the initial breathhold more comfortable. If you want to easily torture yourself a little, exhale fully and with empty lungs do the walk; I find those much more difficult. Practice on the lawn or carpet.

Practice in the water is more beneficial, I think, but getting past the psychological challenges on land should be very helpful as well.

Is your test REALLY with no fins, tanks and no rope to pull on? That sounds kinda ridiculous, to me?

 

[JCM@Atlam]

That is pretty good. I hate practicing static breathhold, so I pretty much never do it. However, a better dry practice is to walk and count steps. I can (usually) do 25 strides (counting each left leg extension) during a casual walk. Learning to do breathold when doing an activity is more relevant (or similar) than laying on a couch.

A few deep cycles helps to remove CO2 and makes the initial breathhold more comfortable. If you want to easily torture yourself a little, exhale fully and with empty lungs do the walk; I find those much more difficult. Practice on the lawn or carpet.

Practice in the water is more beneficial, I think, but getting past the psychological challenges on land should be very helpful as well.

Is your test REALLY with no fins, tanks and no rope to pull on? That sounds kinda ridiculous, to me?

No, it's with fins on

 

[bipolarbear]

I recently (yesterday) sat in on a tdi advanced trimix course. I completed the course last year. The course standards call for a fully geared up, mask off, regulator out swim along a 20m line laid at 6m. Double AL80s with 3x AL40 deco/travel gas.

The instructor advised slow, powerful frog kicks with maximum glide from each kick. The student (GUE Tech 1 I believe) passed without difficulty. I also re-did the exercise: not fun at all but it really is a mental exercise rather than a physiological one, particularly if you understand and appreciate the co2 breathing reflex.

 

[JCM@Atlam]

Thanks. I'm by no means an unfit guy but my first attempt was a disaster! The urge to breath was just too much to resist, but from reading replies I feel I have a better handle on dealing with that now. There's a lot of inertia and drag in all that gear. Rather them than me!

 

[admikar]

Thanks. Efficiency in finning is a common theme across the replies. I need to practice this which should benefit my diving in general as I am heavy on gas consumption.

I think you are getting wrong idea here. It's not about efficiency per se, as in finning technique. It's about resistance.
Water is dense.
Slow down.
You have plenty of time.

 

[JCM@Atlam]

So today I successfully completed the exercise! Perhaps not with great elegance but it's a huge relief that has restored my confidence. The comments here were incredibly helpful, so thanks to all those who contributed.

After removing my mask, I found that taking the time to normalise my breathing with many deep, full breaths, completely expelling the whole lung of gas, before starting the swim, was a major factor in my success. You need to be calm and eliminate as much CO2 from your system as possible to delay the impulse to breathe. I found holding my nose and closing my eyes, also helped.

 

[JCM@Atlam]

To clarify, I inhaled a full breath before I began swimming. The full exhalations were just to purge CO2