I just read about it, basically what you do is suck your stomach in as hard as you can for 60 seconds and do it 3 times i just tried it and i really do think i feel a burn. Anyone else ever heard of or tried this?
I believe the Sargent's got this one. It's something old school bodybuilders would do ( I've no idea what they do nowadays) to build control for posing. There's some usefull carryover as far as breath control for your lifts, but it won't help much in actual ab development.
I dont know i found this site and they said doing this 3 days a week will give great ab results of course with a good diet and a low b/f level alot of people on the site tried it and said it worked. Just something for everyone to try if they want.
Hell yeah Frank Zane used to always do that pose. lol. Haven't seen to many of the new guys do it too much. I think this is what he's talking about as far as an exercise:
There's the key to the idea though. If you have something to show, you'll be able to highlight the effect through increased definition.
Even in the link alex2678 posted, it states that your targeting internal musclature. This is good for support and control, as the article states, but you need to work the outer layer if you want to build on your development.
Ab vacuum is commonly used to work the transverse abdominus, the 'natural weight belt' below the obliques. It is a common exercise in core stability work and a beginner exercise in kinetic chain work. It dramatically improves the ability of the spine to withstand shear forces in the L5 area and usually improves any lower back issues.
Hell yeah Frank Zane used to always do that pose. lol. Haven't seen to many of the new guys do it too much. I think this is what he's talking about as far as an exercise: