Layer your hiking pal with the REI Co-op lightweight long underwear bottoms for kids. Designed for warmth, these bottoms are easy to pull on and wick moisture for comfort.

Underwear BottomsBase Layer Bottoms

Stay halfway to shred-ready by sleeping in the women's NRS Lightweight Union Suit. With midweight insulation and a dropseat for ease, this union suit is key to shoulder season adventures.

UnderwearUnion Suits

Wear the men's REI Co-op Link padded liner shorts under your favorite pants or shorts to make any outfit ready for bike adventures. Plus, the discreet storage pocket on one leg fits a key or your ID.

UnderwearCycling Underwear Bottoms

Make any outfit cycle-ready with the women's REI Co-op Link padded liner shorts. Wear them under jeans, shorts, pants or a dress to make a short ride, commute or serious singletrack more comfortable.

UnderwearCycling Underwear Bottoms

You don't need full bike kit for your commute or a ride to the coffee shop. Pair the REI Co-op Link padded liner shorts with jeans or a dress to get you there and back in total comfort.

UnderwearCycling Underwear Bottoms

When it comes to base layers, basic is better. The men's Lole Logan base layer bottoms are perfect under your gear for outdoor training or activities, or for everyday life.

Underwear BottomsBase Layer Bottoms

When it comes to base layers, basic is better. The men's Lole Logan half zip is a long-sleeve base layer top that's perfect under your gear for outdoor training or activities, or for everyday life.

Underwear TopsBase Layer Tops

With its buttery soft feel and support that's like a gentle hug, the girls' Athleta Long Distance bra might be her new favorite for school, practice and play.

UnderwearSports Bras

Designed with soft, supportive fabric that's great for school, practice and playground time, the girls' Athleta Long Distance 2.0 bra helps young adventurers keep moving in comfort.

UnderwearSports Bras

Great for yoga and training, the Vuori Longline Elevation bra features a dropped neckline, strap details and a wide, comfortable band.

UnderwearSports Bras

Providing lightweight warmth and natural temperature regulation, the Kari Traa Lucie Long-Sleeve base layer top is made from fine merino wool and designed to layer smoothly under your jacket.

Underwear TopsBase Layer Tops

For support on hikes, rides and beyond, choose the Wild Rye Lucille sports bra. It provides reliable, distraction-free support, thanks to carefully placed seams that sit comfortably under a pack.

UnderwearSports Bras

Add a touch of sparkle to your workout with this supportive and comfy prAna Luminance bralette. It's made with stretchy ribbed fabric and a sparkle stripe elastic trim.

UnderwearSports Bras

The Threads 4 Thought Lunette bra is built with crop styling and a racerback to offer just-right coverage that supplies medium support during workouts, and pairs well with high-waisted leggings.

UnderwearSports Bras