I'm 5'10, 145lbs, very active build and long legs- I bought a size small in these (they seem to run big so I'd agree with other reviews and order a size down).I LOVE these tights. Been out running in Minneapolis winter for the past 3 weeks (November and December). For running these are GREAT because you're body's in motion all the time and retains lots of heat in colder weather. They breath really well. In summer, my shorts can get most from sweat and I feel drenched when I get back from a long run. In these, my legs don't get hot at all- I think the fact that the back is not windproof allows everything to breath but keeps you warm (go for a thin layer underneath made of wool material though and you're golden). For walking they might be a little chilly because the back of them is not wind proof and you won't have as much internal body heat to compensate. The only downside is the waist line. I have very muscular legs but a thin waist and can never seem to get the draw string tight enough. After about 3 miles, I have to tug at the waist a bit to pull them. But it's no problem, just a slight inconvenience.Have yet to wear then solo- always have a thin, wicking long underwear layer underneath. Coldest I've run with that layering type is 18 degrees and it was perfectly comfortable. Much colder than that and I'll add a pair of Under Armour Cold Gear- should be good for down to 10 degrees and then Nike Pro Fit that have that slight internal fleece layer that could take me down to zero degrees. I'm surprised by how thin these are and how warm I stay in them running outside in winter- as long as I can stay clear of ice, I could run in Minneapolis year round!

Runs really big. Only the front panels over the thighs are windproof. The back of the tight including the butt is a thin, non- wind resistant fleece. Overall, not a warm tight.

I wore these (always with base layer underneath) for XC skiing last winter. With a warm base layer, they were generally fine except on the coldest, windiest days. I like the wind-blocking panels, but they should be on the backside and the back of the thighs, not just on the front of the thighs. I would prefer more wind-blocking, so I'm still looking for X-C pants for those colder, windier days.

(A note about fit: TNF sizing seems wildly inconsistent. I'm 5'6" tall, was about 115 pounds this past winter, and I needed an XS in these. At 120 pounds now, I can still wear the XS, and might use these to ski on warmer days, but a Small would be better for fitting a thick base layer underneath. For comparison: I just tried on the TNF Apex Big Wall pants in a size 6, and those were too tight in the hips. In other TNF pants I have tried on, the small usually fit. It's all very confusing....)

I worn these tights for snowshoeing and they were very comfortable and warm enough for me. I didn't have to wear another layer, but I was running in the snow and working hard! These are windproof in the front, and water resistant. I got wet in the seat area when I had to slide down the hills but they dried fast. When outside temperature is 0-10 celcius, they were too warm for snowshoeing but they were very breathable so was not unbearable. They fit big, does not fit like "tights" but more like slim "pants". I am 5'1", normally wears small but X-small fits great (not snug), waist band - sits comfortably at waist and length slightly long. Overall, I am very happy with my purchase.

Ordered and returned 'em. I run in Chicago winter and need more than just windstopper-- I need some insulation/warmth the whole way around. I'd rate these to 30 degrees, if that. Behind the windstopper and in the back, they're really thin.

If I could only own one pair of pants in my life, it would be these. Super comfy, great for relaxing, running errands, cycling in rain or wind, running on chilly mornings, hiking and hanging out at the campfire. Can't find any reason not to love these pants. I'm 5'5", 125 lbs. Got the medium so they could fit over my bike shorts, and they are plenty big. If I just wanted to run in them, I'd have gotten a small. They are long in the leg.

I use this product for many indoor and outdoor activities and it works. A great fit that you can wear under pants for skiing, etc., or just wear alone when running errands. Flattering, not body-hugging like others I've tried i.e. Mountain Hardware women's tight. I'm petite, barely 5'3 and around 112 lbs and I went with the XS which was perfect. Nice drawstring waist, zippers at the ankles, high quality craftsmanship and so light it feels like you're wearing nothing. And of course, very insulating from the winds we get here in the Northeast. I had purchased the Mountain Hardware women's tight last year and was surprised at how poorly the product was thought out. You could barely squeeze your legs into the pant only to realize that the waist band had ZERO give making it impossible, and I mean impossible, to get over your hips (again, I'm quite petite). I am in love with the North Face Windstopper tight. A lot of consideration when into this product and I highly recommend it.

I have only worn these pants a couple times and the other day it was about 4 degrees outside, sunny and no wind...and I wore them while taking a walk but because it was so cold felt a need to also put some long underwear on under them. I'm glad I did because my legs still did get cold so they are not as wind proof as I thought they might be. I also think they ran a little big and although I'm usually a medium, I'm quite sure a small would have probably fit better...but I can wear long underwear underneath for added warmth so that's a good thing. Other than that, they are very comfortable and I like them very much !!!