Tank top ride up

[Crankin]

I have the opposite problem. I can't find tank tops short enough for my short body. I just ordered 3 Merrell tanks, from STP, size x small and as soon as i unwrapped the first one, I knew it would be going back. They are at the bottom of my hips/top of thighs and the halter strap is loose and floppy.
If the bottom of the tank doesn't fall in *exactly* the right spot, it makes me look awful. My hips aren't huge, but I am a woman... being short doesn't help this. I noticed that while some manufacturers make petite sized bottoms, no one sells petite sized athletic tops and tanks. This would solve my problem. I don't sew, so that is not an option.
Nike usually fits me, but they are rarely on sale.

[GLC1968]

Terry tanks!

I have the same problem - I'm much larger on the bottom than on the top and just about any tank small enough to provide support rides up with activity.

I have found the Terry tank style tops to work well. I don't think any of them are supportive enough for running, but they work great for cycling. Enough support in the top (if I get the right size) but they flare just enough in the hips that they don't ride up. They are pricey for a tank, but I think it's worth it. My only problem is that occasionally I'll end up with a style that's not quite long enough (I have a long torso) so the little hip flare happens a bit too high up on my waist...but again, it's a small price to pay (and one that won't affect shorter-torso'ed women anyway).

For running, my only option was sports bra with a looser tank on top. Or in my case, give up running altogether!

[Crankin]

Yes, I have given up on finding a running/yoga specific tank that fits me. I wear my Terry Eurohalters for it all. Sometimes, the pocket gets a little curled up under me in yoga, but you are right, they do fit well on the bottom. Since I have almost no chest, support while running isn't an issue. I bounce a little, but nothing noticeable!
You can get the Eurohalters really cheap in the winter; like half price.

[VeloVT]

I am built similarly and have had good luck with the Sugoi Fizz Tank.

and TE carries them...

[Reesha]

I actually have a fizz tank and while it's great for general working out and biking some, I am totally stuck for running. I have a size large and it doesn't ride up, but I have to wear a sports bra under it cause it's almost baggy on my chest!