rubber legs after a mix of 02 tables and negative dives

[maltaspearo]

last monday i was practicing o2 tables in a 15 foot pool.i did my first three breath holds of 2.00 2.15 2.35 then i continued with two compleatly empty lung dives at 15 feet for 35 and 40 seconds. and imidiatly continued with 4 more breath holds of about 2.30 3.00 (IM STILL A BEGINNER)
AFTER I FINISHED THE SESION AND GOT OUT OF THE POOL I HAD REALLY RUBBERY LEGS AND COULD BARLY WALK DOES ANYONE KNOW WHY.HAS THIS EVER HAPPENED TO ANY OF YOU.WAS I IN RISK OF A B.O OR SAMBA. IT FELT SORT OF LIKE AFTER DOING A BUNCH OF SQUATS. YOU KNOW HOW YOU THIES AND HAMSTRINGS FELL LIKE RUBBER AND YOU CAN BARLY WALK. SAME FEELING

 

[Pezman]

Malta,

It could be a depletion of creatine and lactic acid build-up since any muscular effort in apnea tends to cause exaggerated increases of lactate (i.e. there is not enough oxygen to permit aerobic metabolism, so your muscles rely on anaerobic metabolism). If you recovered quickly, that's probably the explanation.

There is another possible explanation involving a pressure injury. I recently suffered a mild injury from a 130' dive (which is quite deep for me) that I performed w/o sufficient warm-up. My guess is that the injury was caused by a number of factors in combination:
- the fact that peripheral blood vessels had not yet constricted (i.e. mamalian dive reflex not yet in effect)
- the fact that I was not well hydrated
- the increase in blood pressure that accompanies hypoxia
- an overly rapid ascent

After this dive, I had a dry cough, mild chest pain, could not hold my breath for more than about 30 seconds and also had a splitting headache. After researching this a little, it seems like the symptoms were very similar to a mild case of HAPE (high altitude pulmonary edema) and HACE (high altitude cerebral edema). My guess is that the increased cardiac output, overly thick blood and a rapid decrease in pressure in my peripheral body parts caused an abnormal pressure gradient across the vessels in my lungs and brain, and the result was mild edema. What is remarkable about this is that I'm reasonably certain that it was the ascent that cause the injury and not the descent adn I think that this is contrary to common wisdom about "squeeze" injuries.

The reason that I mention this is that I think that negative pressure dives could cause a similar effect and the relative pressure increase from even a modest depth like 15' is substantial. If the rubbery legs lasted for a long time, then it could be a pressure injury, and you might want to give it some time.

I am more or less recovered form my squeeze, but I intend to take a week or two off from apnea sports. I tried some statics yesterday and almost immediately had a resumption of mild symptoms (tightness in chest, dry cough etc.).

 

[OceanSwimmer]

Hi Pez,
---Where were you diving? And could you direct me to the resource for the physiological information? I'm interested in the changes in metabolism during apnea diving.
Hope you recover soon. Be careful down there!
OceanSwimmer

 

[Pezman]

Ocean,

We were in Wabank quarry, which goes to about 142'. JimGlynn got to the bottom, which caused me to get a little more revved up than was wise.

As far as relevant physiology, the keywords "HAPE" and "HACE" (high altitude pulmonary edema and cerebral edema respectively) will turn up a ton of information. The stuff about the injury occurring on ascent is conjecture on my part, but I think that it makes sense since the venous systems ensures blood flow in one direction (i.e. if you get a pressure differential, the blood flow required to alleviate the difference must traverse the lungs).