X-Bionic Energizer T-Shirt - Long-sleeve - Women's - 2009 BCS

I was first introduced to X-Bionic in Europe, and I almost had a heart attack when I found out how expensive these baselayers are. The technology behind the products is truly innovative and cutting edge, and I definitely think you're paying for that technology. It's very much worth going to the company's website and learning more about their concepts. I was lucky to find this shirt used on Geartrade for a fraction of the retail price, so I was able to try it out without such a massive investment.

I am an extremely heavy sweater regardless of the air temperature, so I think I'm a good test candidate for this type of shirt. The first time I wore it (hiking up a 14,000 foot peak in CO this summer) I was blown away. It really works. It really disperses the sweat away from your high-sweat areas and never feels wet against your skin (even though you can see the sweat stains on the fabric). And with wide temperature variations between the base of the mountain and the summit, the air was hot at the bottom and freezing cold at the top. This baselayer is great for these kind of varying conditions since it will cool you down if you're hot or keep you insulated if you're sweating in the cold.

I really think the technology is amazing. If you're one of those people like me who sweats so much during cold-weather highly aerobic activities and end up close to hypothermic if you stop because your baselayer can't keep up with your sweat rate and you cool down really fast, an X-Bionic shirt might be for you.

I've had this shirt for almost a year now and it is such an interesting and functional shirt. I am usually pretty skeptical of the claims of superior performance made by most clothing companies, but in the case of X-Bionic, I find the claims to be totally justified. The unique weave in the strategically placed positions really does seem to be able to pull moisture quickly to the surface to evaporate. I sweat a lot, so anything that doesn't end up drenched at the end of a run is pretty impressive in my book. This is my go-to winter running shirt (best under an Icebreaker 1/4 zip or my Salomon Azimuth jacket). The fit is body hugging without feeling restrictive, which makes it a perfect layer for other cold weather aerobic activities as well (I occasionally wear mine as a baselayer when snowboarding). I have the S/M and feel like it fits true to size (I'm 5'6" 130-135lbs).