Shock Absorber Impact Level 3 Anti-Bounce Sports Bra, $46
Why we liked it: When you put this bad boy on, you get the sense that someone spent a long time in front of the old drawing board. First, nearly the whole thing is made out of CoolMax, so any "moisture" hardly has a prayer before being wicked away from the body. Plus, there are all sorts of seams intended for maximum support. Unlike other slip-on racer-back sports bras, Shock Absorber's has adjustable side panels to find the perfect fit.

What you should know: For all that forethought and the amount they're charging, it seems like it should work better than it does. The tank-with-a-keyhole design may be sexy or serve some function we couldn't discern, but it felt strange to leave the top and middle of the breasts exposed. And by strange we mean flimsily supported. The bra's "overalls" design ‑- a panel on the front and then a second one coming from the back over the shoulders ‑- made us feel like our breasts were forced downward instead of into the firm and perky illusion some of the other bras offered.

Old Navy's Sports Bra, $10
Why we liked it: For the money, you won't do any better. Sure, you're not going to get any fancy technology with this plain tank bra, but it's supersoft against your skin and gets the job done sufficiently. The CoolMax lining lifts moisture away from the body to avoid the dreaded postworkout chill. And, unlike the more structured and complicated boulder holders, you could definitely wear this bra as a stand-alone top.

What you should know: Women with more to, ahem, work with should buy a size down, because after wearing this bra for about an hour, it conforms to the body, stretches and loses some of its holding power. Aesthetically, the design is cute and offers pretty good support overall, but no matter what size you buy for the foundation factor, the extra-low scoop neck leaves some places ‑- top and sides ‑- more vulnerable to the bounce than others.