When you get hot and sweaty at the gym or working out in the heat they stay cool and they dry fast unlike cotton briefs
592640
Everyone should at least try one pair you pay a little more but it's worth every penny. When you get hot and sweaty at the gym or working out in the heat they stay cool and they dry fast unlike cotton briefs.
90604
I bought these to work out in, they are loose so your body can breath and you don't feel restriction.

Didn't shrink much after washing, will be purchasing more.
2899882
I have several of the Under Armour underwear, and after switching to them four years ago I'll never go back to cotton.

The breathability is excellent, especially with the mesh area in the pouch.  Even when doing the sweatiest activity, exposing them to a little air wicks the moisture right away.  I ride a motorcycle, and even when soaked through in rain, these dry out very quickly allowing you to get the miles in.
4624900
These are magic, I have worn them under clothes in temps from 30 - 72 degrees and have stayed feeling comfortable and not sweaty and sticky while at rest and during physical activity.  I generally wear these while training martial arts which is standing then bursts of physical activity, or while running for 3-4 miles.

I have tried a few different brands such as Nike, underarmour, even cotton ones and every single one of those has a small temp range where they are comfortable with little movement but can't handle moisture wicking once you start either short bursts of activity or sustained activity.
2688648
The X-Temp is great for those that sweat. They dry quickly and aren't as gross when wet. The newer ones don't have the permanent crease the old ones did.
2750083
These keep me cool and dry during my lifting routine. These have plenty of stretch and won't tear during squats or dead lifts.

These sit tight on my thighs (by choice) and while I exercise they don't slide up unlike under armour options have tried.

I got some pairs at $12.50 each, which is what I believe is the lowest price offered so if you see the price at that then order right away.
298444
Undershirts get soaked I love that this shirt kept me dry even under the desert heat I work in daily
848043
I wore the black version of these briefs and they'e awesome!  They stay dry and feel nice and cool. Lots of support!
1291313
Cool, light, breathable fabric. Definitely cooler and wicks sweat better than cotton tees.
3853133
Holds sweat like you wouldn't believe, this item is great, glad I bought the 2 pack
2273132
Very good and comfortable short to workout in. I'd recommend working out in this if in a hot environment because it will keep you cool.
2530082
I didn't think I would like these at first because they fit a little tighter than the regular Fruit of the Loom boxer briefs I normally wear, but after getting used to them, I actually like them better.
They stay noticeably drier when Im sweating.
652124
These are great boxer briefs, and stand up to everyday use.  The best thing about them is how comfortable and lightweight they are, especially for working out.  Because of the wicking wool does, these boxers never get too hot, and are cool/comfortable compared to traditional cotton.  My only feedback would be a slightly higher cut, as the leg portion comes down a little further than I'm used to.
2461070
These are fantastic! They are comfortable and stay in place during my high intensity cardio class as well as during Yoga and Pilates. They do a great job of wicking away moisture. I would highly recommend these
4221275
I purchased one pair each of 3 of the top brands of boxer brief ~5 months ago to do some user testing. I am a 5'8", 190lb male competing in amateur Strongman. I lift and carry a decent amount of muscle in my hips, ass, and legs. I work at a gym and coach lacrosse and was looking for something that would keep me reasonably cool, dry, and comfortable during my day of moving around and sweating.

UNDER ARMOR ORIGINAL 6' BOXER BRIEF
The worst of the group. It looks like they left room for an athletic cup in there, but it holds my package really weirdly and is uncomfortable beyond about 10 minutes. Fits nicely on the legs and waist, doesn't tend to ride up, but the package-mashing effect drops it way down my list. The material is also rougher than the other two reviewed. Wicking and dryness was adequate.

ADIDAS CLIMALITE "SPORT PERFORMANCE" BOXER BRIEF
Slightly better than the UA brief, material is softer, but they run small. More comfortable overall, but there still isn't enough room for the package. One thing that I noticed with the boxer briefs as well as with compressions shorts is that the comfortable brands have a square stitched in to the taint area. Without this extra patch, the material pulls around the taint like a thong. While some may find this strapping-down effect beneficial, I like to have a bit more room and prefer the square patch.

EX-OFFICIO MEN'S "GIVE AND GO" BOXER BRIEF
This was the best of the 3 and the only one that I bought more of. They fit nicely, the material is comfortable, the wicking is excellent, and my package is secure but comfortable all day. They are a little more expensive than the other two, but well worth the money. They ride up a bit because they are less compressive than the UA and Adidas, but never to the wedgie point of discomfort. I generally wear these for a day and then hand wash them in my sink at night, and they're dry by the next day. Supremely efficient and comfortable as well.

CONCLUSION
If you want compression shorts for working out, go buy some actual compression shorts. I prefer the ones made by Under Armor with the square taint patch because it keeps the material from tugging on my Johnson. If you want an every-day boxer brief with excellent wicking and overall comfort of both legs, ass, and Johnson, buy the Ex-Officios. UA and Adidas both tried to create a combination compression short and boxer brief and ended up not doing either very well.
2681135
I wear these because I sweat a LOT when I workout and need a fitted shirt to keep me (somewhat) dry.

I'm 5'9", 155 and the medium fits great. No chafing, rubbing, etc. After 3 months of use, they have yet to retain any sweat smells.

NOTE: After I use them, I rinse with cold water, wring them out and hang to air dry. Then I put it in my pile of "athletic clothes laundry" and run that off within the week.

I recommend these! For $12.99, it's a steal.
2500265
Love these underwear!  They will definitely replace my cotton underwear, although they are more expensive.  However, they do a great job of staying cool in hot, muggy temperatures, and they definitely do a great job of preventing odor!  It won't stop several days of vigorous hiking from smelling bad, but it does a great job on day-to-day walking w/ light sweating, etc.  Slowly buying more.