Sensations during uddiyana bandha?

[sai]

I just started to do some light uddiyana bandhas to increase my diaphragm flexibility. Basically they're just like full exhale static except pulling the belly up. I get quite a heavy body response after just 15 seconds, my face turns completely red and I can feel the pressure rising in my head. It doesn't really feel comfortable and I guess these sudden blood pressure spikes aren't that healthy. Is this common and/or harmless?

 

[growingupninja]

I just started to do some light uddiyana bandhas to increase my diaphragm flexibility. Basically they're just like full exhale static except pulling the belly up. I get quite a heavy body response after just 15 seconds, my face turns completely red and I can feel the pressure rising in my head. It doesn't really feel comfortable and I guess these sudden blood pressure spikes aren't that healthy. Is this common and/or harmless?

I didn't know that it was a yoga thing but that is how I neg pack stretch--sit crosslegged, fold at the waist to floor, exhale, neg pack, then straighten and suck in abs and start to stretch. I always experience fairly strong brachycardia and some vasoconstriction when I do these.. Both of which usually associated with a rise in blood pressure. Somebody correct me if I am wrong but I am pretty sure almost all apnea activities cause an increase in blood pressure.

 

[RPGgrenade]

I'm not sure if it's unhealthy, but i've been able to do the uddiyana bandha since i was around 10, (currently 19) and it's not the only weird exercise i use for it, I also use the Nauli and Nauli Kriya (though i don't know if that's their real name) which has to with increases the stress factor by tightening your abs with hands supported on your thighs. I don' t know if it helps with the flexibility, but i could do it easily so i figured i'd give it a go. if it's painful to keep doing it i don't think you should continue not breathing, i usually just move around a little bit after 45 seconds so i can do the nauli and stuff...