negatives and tingling arms

[cdavis]

Here is a question for those more physiologically knowledgeable.

I do 5-10 negatives at the beginning of each pool work out. Short dives, max 40 seconds including time to exhale and reverse pack, 4 meters depth. Short recovery. The first 2 or 3 dives I get an intense urge to breathe, tingling in my forearms and dead feeling legs. Feels hypoxic. Subsequent dives, this all passes as the body shifts to dive mode. After this, i do a dynamic in which I can feel a good blood shift, burning legs, late urge to breath, good distance.

What is the tingling? It acts like maybe a massive blood shift, but, if so, why does it stop tingling after 3 dives?

Thanks

Connor

 

[jimdoe2you]

Are you hyperventilating prior to your negatives? If you are, there is increased sensitivity and irritability of neuromuscular tissue, due to an elevation in blood pH, which gives rise to a superficial tingling of the extremities.

If we're lucky, Eric Fattah will catch wind of this thread.

Jim

 

[cdavis]

Nope, a couple of purge breaths, no hyperventilation. This is a different type of tingling, the head is not involved, not the same as caused by low co2 and doesn't seem like the associated urge to breathe would be consistant.

That is a good explanatory diagram, where is it from?

Connor

 

[DeepThought]

Sounds to me like good blood shift, but I usualy don't feel mine so just from other poeple's description.

 

[trullalla]

i have the same happening to me, but only during FI dives.
at turnaround point i start feeling a very strong tingling in the feet, and then legs and finally in the arms. the head in unaffected. i don't get the same in cw, even though i dive deeper in constant than in free immersion.i guess this is because not using the legs at all allows much more blood to be taken away from them. i don't get any of it in negatives, but usually my negatives are not long or demanding, and then again i use my legs to swim back, so there could be not enough moving blood to create a noticeable effect.

i dont' know the reason why you don't feel the tingling anymore after the first dives. but i can guess that if you do a lot of negatives without increasing the depth, at some point you will reach the max bloodshift you can get for that depth, and blood will stop moving away.

hope it's clear.

cheers
linda

 

[cdavis]

Interesting idea, Linda, thank you. It does seem to be blood shift, but I don't think we have quite figured out what else is going on.

Is it possible that some part of the dive reflex, other that blood shift, is kicking in and adapting the legs and arms to low blood flow? Alternately, does the blood shift modify itself to get less and not starve the arms and legs? I know I get less blood shift in dynamic after 3 negatives rather than 6 or 8.

Anybody else know of any threads that might throw light on this?

Thanks,

Connor

 

[efattah]

The tingling described is definitely blood shift related, and it is very desireable. Sometimes it can happen at the end of a deep dive as well, but during intense negatives it is most common.

 

[Mullins]

Is a strong 'gripping' or tingling sensation around your lower back/kidney area also related to bloodshift, or would it be something else entirely? I get this on my left side only, at about the 2 min mark when doing statics. It remains for about 2 mins and can be quite intense, like somebody is standing on my kidneys.

 

[efattah]

Maybe it's your spleen? Your spleen contracts during hypoxia.

 

[trullalla]

Interesting idea, Linda, thank you. It does seem to be blood shift, but I don't think we have quite figured out what else is going on.
Is it possible that some part of the dive reflex, other that blood shift, is kicking in and adapting the legs and arms to low blood flow?

hi Connor,
other than bloodshift (which you get during negatives or deep diving) you will get a vasoconstriction following breathholding and/or immersion in water.
if you get a strong dive response your muscles start working anaerobically, and this is how your body deals with the lack of oxygen in your legs.

how many dynamics are you doing after your series of negatives? just one max?

cheers
linda

 

[cdavis]

Linda,

I think you are right. Without understanding exactly what is going on, it seems like the tingling disappears as the body adjusts to a low 02 environment. I can't think of any reason I would get less blood shift from sequential negatives.

I always do at least one dynamic, at least 75 yrds, after negatives. I may follow that with a series, working towards 100 yrds or doing a mixed set of swim 25, hold for 10-40 sec, swim 25-50. I don't have a spotter, so don't push and involve the guards in my practice. This only works when the pool is almost empty.
Something I don't quite understand, the negatives seem to kick in only part of the dive reflex. The first dynamic is hard to recover from, takes a long time, legs burn like heck and isn't my best distance. If I do a series, they get easier, longer, and recovery times get shorter. I think I'm getting less blood shift because my legs burn less. This tends to make me a little paranoid, so I cut it off early.

Connor

 

[trullalla]

Connor,
i think that after such a warm-up (repetitive negatives), you would get your best performance during your first dynamic. if you say that your legs burn than it's a positive sign (even if it feels horrible!), especially if you notice that your head is 100% clear (sign that you are not hypoxic). the legs burn because of the lactic acid produced by the anaerobic exercise.
if you start doing repetitive dyn, at some point (quite soon) you'll lose the benefit of the dive reflex, legs don't burn anymore, but if you go for a max then you should have worse results. but then again, if you don't have safety available you don't do a max, and then comparing non-max dives is a bit useless.
hope it's clear.

cheers
linda

 

[cdavis]

I would have thought the same thing, but it doesn't seem to be that way. My C02 tolerance is lousy and that is what stops my dynamic any time I really go for it, no matter how many negatives or how good a blood shift I get. I don't notice feeling hypoxic (well, once) in my head. I agree with you that the blood shift effect of negatives gets less as you exercise, but something else is going on here that makes for better performance after a few runs. I wish I understood what.

Connor