Spearing & Lung Packing

[Trelos]

Hi guys,

I have been spearfishing for about a year now (Greece) but I wanted to improve my bottom time and depth so I trained for the second level CMAS freediving certificate. It helped me to improve a lot as I am now able to spear comfortably at 15m (previously 10m was a struggle). The thing is I would like to spear deeper (around 25m) comfortably (total dive time close to 2 min.)

I’ve been reading about a technique called lung packing. I’m pretty sure I’m doing it properly as when I pack around five times it feels like my chest is going to explode.

I tried to see if I would benefit from packing in dry statics but I couldn’t even reach 2 minutes because the pressure made me feel very uncomfortable and contractions started way earlier than without packing (my PB without packing is 4 minutes).

• I understand the main benefit of packing is to have more air to equalize at depth.
• Could a second benefit also be to hold more air comfortably at depth, not just to equalize?

Let me explain the second benefit. On the surface, someone with 8 liters lung capacity would feel uncomfortable with 3 liters of packing (total 11 liters). After diving past 10m, the 11 liters shrinks to 5.5 liters or less with increased depth which means that the lungs are no longer stretched passed the norm of 8 liters. Does this mean I will be comfortable with packing after a certain depth (because pressure in the lungs decreases) or have I got the physiology wrong?

If the above is correct, then packing would be beneficial to a spearo as it would make dives longer, allow for comfortable diving and allow deeper dives.

In addition, does this mean that apnesist would potentially be able to break static records at depth because far more air would be able to be packed with no pressure side effect?

(say 5m, more depth I assume would be counter productive as a lot of oxygen would be used up in dynamics to reach the depth and of course to equalize)

Your comments would be appreciated.

[spearheads]

Originally Posted by Trelos

Hi guys,

I have been spearfishing for about a year now (Greece) but I wanted to improve my bottom time and depth so I trained for the second level CMAS freediving certificate. It helped me to improve a lot as I am now able to spear comfortably at 15m (previously 10m was a struggle). The thing is I would like to spear deeper (around 25m) comfortably (total dive time close to 2 min.)

I’ve been reading about a technique called lung packing. I’m pretty sure I’m doing it properly as when I pack around five times it feels like my chest is going to explode.

I tried to see if I would benefit from packing in dry statics but I couldn’t even reach 2 minutes because the pressure made me feel very uncomfortable and contractions started way earlier than without packing (my PB without packing is 4 minutes).

• I understand the main benefit of packing is to have more air to equalize at depth.
• Could a second benefit also be to hold more air comfortably at depth, not just to equalize?

Let me explain the second benefit. On the surface, someone with 8 liters lung capacity would feel uncomfortable with 3 liters of packing (total 11 liters). After diving past 10m, the 11 liters shrinks to 5.5 liters or less with increased depth which means that the lungs are no longer stretched passed the norm of 8 liters. Does this mean I will be comfortable with packing after a certain depth (because pressure in the lungs decreases) or have I got the physiology wrong?

If the above is correct, then packing would be beneficial to a spearo as it would make dives longer, allow for comfortable diving and allow deeper dives.

In addition, does this mean that apnesist would potentially be able to break static records at depth because far more air would be able to be packed with no pressure side effect?

(say 5m, more depth I assume would be counter productive as a lot of oxygen would be used up in dynamics to reach the depth and of course to equalize)

Your comments would be appreciated.

i am not sure but is nt packing dangerouse when diving

[Trelos]

I think theres no danger from packing moderately..

[efattah]

You are correct. The discomfort from packing goes away once you get deep. It does allow longer dive times but it can increase the risk of squeeze injury at depth for complicated reasons. If you are prone to lung squeeze I would be very careful. Packing for deep dives also increases the risk of DCS (for dives over 30m).

When doing statics, it is possible to learn to become comfortable with the extra air. Doing static at depth makes it more comfortable, but the CO2 level increases dramatically and makes static at depth very hard.

[Trelos]

Thanks Eric!

I was hoping someone with your experience would shed some light on this.

I guess I'll pack moderately for deeper than usual dives (for me this is 18m plus, not near the 30m mark yet). I do alot of ambush spearing and even an extra 12-18 secs benefit from packing would make all the difference.

If I pack half of my max, is there still danger from lung squeeze at 20-28m depth?

Cheers

[spaghetti]

What does packing mean? (I'm still improving my diving-english and I lack many technical words, so please anyone explain to me what is this about)

[Trelos]

Basically, when you take a full inhale/breath of air you try to swallow more air on top of what your lung capacity is through a series of shallow breaths using the cheeks as a piston.. (search the forums for more info - it took me a while to get it right).

[spaghetti]

Thank's mate, now i understand: it must be what we call "manovra della carpa" in our language (the carp's manoeuvre). It is no longer recommended in my country's diving schools for lung squeeze problems. But you said you will do it "moderately"...

[efattah]

Avoiding lung squeeze requires that the capillaries in the lungs swell with blood. When you pack lots, this pushes the blood AWAY from the lungs. Once you start the dive, if you go down very slowly, the blood will return to the lungs.

The biggest danger of squeeze is to pack lots, and then dive down very fast. One of the most important techniques to avoid squeeze is to descend slowly, especially in the first 10-15m. Most people find that descending slowly (very relaxed) in the first 15m results in the longest dive anyway, so it should be fine.

DCS can still be avoided if you pack, but you must start keeping track of your nitrogen levels if your dives start becoming near 30m and very long. From my own experience, if you are doing 2'00" dives to 30m, you should take at least 7'00" rest at the surface, and do no more than 8 dives maximum in one day (even that is pushing it). I got DCS after nine dives averaging 2'44" to 24-38m, (with the average depth being 33m), with surface intervals of 6'45".

Even if you don't get real DCS symptoms, if you are always 'close' to DCS, you are suffering long term damage all over your body. This is why you must stay 'far' from DCS.

[Brett Craik]

Trelos,

You don't need to bother with all that, I can spear fairly comfortably at 20 - 25 metres and I exhale half my air on descent, so why bother with packing?

Cheers

[Trelos]

I am sure most people packed to their limits so they increased the problem of lung squeeze dramatically. I also dont intend to spear in the 30m+ zone in the near future.

I think moderate packing should ok for my purposes. Maybe packing regularly stretches the tissues reducing the effect of lung squeeze. Nature always seems to make the body adapt to non-natural situations so it wouldnt surprise me..

[Trelos]

Originally Posted by Brett Craik

Trelos,

You don't need to bother with all that, I can spear fairly comfortably at 20 - 25 metres and I exhale half my air on descent, so why bother with packing?

Cheers

Why do you exhale? I dont understand that technique..Do you hyperventilate to make dives to 20-25m comfortable? I assume your dives in the 2min zone.

[Trelos]

Originally Posted by efattah

Avoiding lung squeeze requires that the capillaries in the lungs swell with blood. When you pack lots, this pushes the blood AWAY from the lungs. Once you start the dive, if you go down very slowly, the blood will return to the lungs.

The biggest danger of squeeze is to pack lots, and then dive down very fast. One of the most important techniques to avoid squeeze is to descend slowly, especially in the first 10-15m. Most people find that descending slowly (very relaxed) in the first 15m results in the longest dive anyway, so it should be fine.

DCS can still be avoided if you pack, but you must start keeping track of your nitrogen levels if your dives start becoming near 30m and very long. From my own experience, if you are doing 2'00" dives to 30m, you should take at least 7'00" rest at the surface, and do no more than 8 dives maximum in one day (even that is pushing it). I got DCS after nine dives averaging 2'44" to 24-38m, (with the average depth being 33m), with surface intervals of 6'45".

Even if you don't get real DCS symptoms, if you are always 'close' to DCS, you are suffering long term damage all over your body. This is why you must stay 'far' from DCS.

Eric,

Most of my spearo budies do dives in the 25-30m range and they do it for more than 3 hours with 6-7 min intervals. They do way more than the 8 dives you suggest but non of them pack and their total dive time is in the 1:30-1:50 range. Are they still in danger from DCS if they dont pack?

I also spear for 3-4 hours in the 10-18m range with 5 minute surface intervals but I dont feel strange or have any symptoms of DCS. You sure you didnt have a really short surface interval somewhere between?

[DeepThought]

Trelos, do a search on 'pack stretching', this can help lots with discomfort and pack injuries.
Better go slowly and gradualy with packing.
Packing can also cause packing blackouts, be careful. I don't think I would like to implement packing into serial diving. I hope you have a buddy who really watches you and not just spear near you.

[Brett Craik]

Trelos,

I exhale for several reasons, firstly it removes bouyancy, meaning I can drop down in weight (I can shed approximately 60 - 65%) and I can descend with only 2 or 3 strokes of my free arm, the legs are much bigger muscles to activate them at the start of the dive is like putting a puncture in a tyre, they will continue to burn oxygen during the dive. The reduced weight makes returning to the surface easier at the end of the dive, also a factor of exhale diving is you recover between dives much faster hence you can do more dives in a days hunting. And lastly Blackout is significantly less likely due to the removal of the expansion(lungs stealing oxygen the brain needs) at the end of the dive.

Its not an easy technique to perfect as you need to progress the depths slowly, however if you have the time I would suggest you give it a go.

Oh and comparing it to inhale diving which I used to do, it's just more enjoyable you feel like you belong there is no fight to get down and get back up.