These are in all reality just long underwear, but I have to admit that after the first few days I wore these I was happy. I can not claim that they made me perform any better, but I never noticed them, stayed worm, and felt clean at the end of the day. For me, that is all I can ask from a pair of long underwear. Worm equals happy.

I recently decided to give Under Armour base layers a try and they are amazing. They quickly and efficiently move perspiration away from your body, leaving you dry and warm. These things are so efficient at moving water that when I remove them from the washing machine they are close to being dry and take about 15 to 20 minutes to hang dry.

Wore these along with the 1/4 zip top (not sold here, unfortunately) during a mid-October weekend in the Adirondack High Peaks region. Under a pair of hiking pants, these will be all you need in fair weather and temperatures ranging from the low 50s to right down around freezing. While active, the top is all you need for similar weather. My only gripe is that the size I got (medium) were a bit short on me in length. If you're around 5'10" and about 145-160ish, consider ordering a size up. Other than that, the material is very lightweight, extremely breathable, and dries very quickly - everything you ask for in a lightweight base layer.

These tight fitting lightweight undies performed perfectly for me even in temps in the teens. I purchased them for use around campus in the winter. My hope was that they would insulate moderately while walking from building to building outside, but not cause me to over heat while in class. They have worked excellent! Remember that these are actually for warmer temps and are not ideal for extended periods in the extreme cold.

These are my leggings of choice for hiking and biking in Spring and Fall when the temperatures are above freezing. They are very good at wicking away moisture and keeping me warm and dry. I not recommend these for really cold adventures. Fit is true to size.

I live in upstate NY where it can get pretty cold and windy. I needed a light pair of thermals to wear under my dress pants or scrubs for the ~10 min walk from my house to the hospital. I have a down coat that I wear for the winter but it's a jacket so my lower half freezes on the walk (i refuse to wear a parka). I used to wear the medium weight thermals I use for skiing which was fine for the cold but then I would become too warm indoors and have to go through the hassle of taking them off. These 1.0 thermals are the perfect solution. They are warm enough to make the walk outside bearable and yet comfortable and light enough for me to wear inside. They are also quick dry and odor resistance which is an added plus when I wear them all day.

Sizing details:
I'm 5'10.5", 145 lbs and I bought mediums.

I wanted a base layer that I could wear outside and yet be comfortable when inside. It has been single digits this week in Chicago, and I have been comfortable wearing these while walking to the train (about a half mile) and then leaving them on, under my suit pants, during the day in the office. Looking forward to wearing them on a backpacking trip too.

I use these on warmer days and when I'm touring. They do a great job keeping me warm, but I never overheat in them. They do a great job regulating temperature, wicking away perspiration, and they don't absorb odor either. My only complaint is that I like a really tight fit with baselayers, and they fit well except around the ankles, they are a tiny bit loose. Otherwise, these are great.

I took these to a recent snowboard trip to Colorado. The temperatures were in the 30-40s. My legs were plenty warm (and sweatfree) when worn under snowboard pants. I'm 5'7", 160 lbs and a medium was a nice, snug fit. If the temperatures were a little colder I think I would have needed something a little thicker.