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Janji Collective

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Womens Fit Guide
biodegradable
run everywhere
guarantee
free shipping on
orders over $75
free 60 day exchanges
+ no-fuss returns

Runterra Bio Muscle Tank

Runterra Bio Muscle Tank

COLOR >>  
W's Runterra Bio Muscle Tank
size >>
style >>

Hurry, only 1 left in stock!

THIS PRODUCT IS ONLY AVAILABLE TO JANJI COLLECTIVE MEMBERS

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JOIN JANJI COLLECTIVE

THIS PRODUCT IS ONLY AVAILABLE TO JANJI COLLECTIVE MEMBERS

Join now to unlock access

JOIN JANJI COLLECTIVE
run everywhere guarantee
free shipping over $75
free 60 day exchanges
Justine is 5’7” // she wears size SAlexis is 5’9” // she wears size MTalia is 5’8” // she wears size L Relaxed fit, Size Chart

Run in it, sweat in it, live in it — then biodegrade it!

The first synthetic-blend running shirt that biodegrades like a 100% cotton tee, our Runterra Bio offers the enhanced moisture and odor control of specially-formulated 37.5® polyester with the comfort and versatility of cotton. This innovative fabric breaks down into organic compounds in as few as four years. Conventional polyester takes up to four hundred.

Don’t sweat it  this tee will only start to biodegrade in anaerobic (oxygen-poor) environments. It breaks down in the landfill, not in your closet.

Explore more

features

Biodegradable
Runterra Bio is powered by a specially formulated 37.5® polyester with enhanced biodegradation to break down into bio-based compounds in as few as 4 years in an oxygen-poor environment like a landfill

Premium cotton
Made from long staple, US-grown Supima® cotton for superior softness, strength + durability

Everyday looks
Easy to wear, slightly cropped silhouette hits above hip

Active comfort
Blended with 37.5® polyester, a special technology utilizing the natural benefits of microscopic volcanic ash to provide enhanced thermal, vapor + odor regulation to maintain body comfort during activity

Wear more, wash less
The natural odor resistance of cotton is boosted by the volcanic particles which "trap" odors so you can put this top through repeated wear

Modified raglan design
Shoulder seams are rolled back off the top of the shoulders for ergonomic comfort

Shrinkage is natural
This top is made from 70% natural fibers and is not pre-shrunk so some shrinkage may occur, up to half a size

materials + specs

Runterra
70% Supima® cotton, 30% 37.5® tech polyester

Garment made in Vietnam

Weight
103g / 2.6oz (W’s Small)

sustainability

Why do biodegradable synthetics matter? 

While we design Janji gear to last and hold up to the demand of years of running, no tee or running shorts should last forever. With this in mind, we are researching innovative ways to improve end-of-life cycle management of our apparel. While we look into longer-term solutions and circular methods — recycle, repurpose and reuse programs — we also know that most textiles are thrown out and end up in landfills. Conventional synthetics, used heavily in active apparel for their high-performance functionality, do not biodegrade in typical landfill conditions. This includes synthetics made from recycled materials, and is why most plastic seemingly lasts forever.

We are seeking solutions to fix this as a performance apparel company that relies on synthetics, including the use of non-ecotoxic biodegradability within our textiles like this new Runterra Bio. This is the first step on a better path forward.



Runterra is made from premium, long-staple Supima® cotton which is 50% longer and up to 45% stronger than other cottons (and softer, too). The stronger the fiber, the more durable the garment, and therefore the more it can be worn. Supima® cotton is grown by a select few family farms that utilize advanced water and soil management techniques to reduce consumption and ensure the health of the land for optimal renewability.



Runterra fabric is also OEKO-TEX® certified, meaning it is free from harmful chemicals and is fabricated in a way that meets a high environmental standard.



 

Learn more about our sustainable initiatives here.

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Customer Reviews

Based on 13 reviews
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J
Jackie L.
Wear it for: Running
Product Fit: Runs large
Height: 5'0" or shorter
Usual Size: S
Size Purchased: S
Great for Running

I loved this muscle tank; super comfortable and light, plus no chaffing. I got the S, but the XS would probably have been a better fit. I highly recommend it.

N
Nancy C.
Wear it for: Running, Hiking, Everyday wear
Product Fit: Spot-on
Height: 5'4" to 5'6"
Usual Size: S
Size Purchased: S

Fabulous tank for running. Lightweight, doesn’t chaff, and the box fit lets air circulate. Nicely stink resistant. I went to buy more, but they were all sold out. Hopefully more next summer.

P
Pamela
Wear it for: Running
Product Fit: Spot-on
Height: 5'4" to 5'6"
Usual Size: S
Great top for the summer

I love the simplicity of this top. It's loose, comfortable, and great in hot weather!

K
Kayla B.
Wear it for: Hiking, Everyday wear
Product Fit: Runs large
Height: 5'1" to 5'3"
Usual Size: S
Size Purchased: XS
Cute & comfy

Bought this primarily just for everyday wear. It’s really comfortable and light! I typically wear a small in most clothes but based on the way it looked on the model i ordered an extra small and it fits as pictured!

V
Vanessa
Wear it for: Hiking, Camping, Cycling, Mountain Biking, Everyday wear
Product Fit: Runs large
Height: 5'10" to 6'0"
Usual Size: S
Size Purchased: XS
Perfect top for cycling or post run

Super soft, great design, excellent message. Super cute boxy and slightly cropped fit. I like these and the tee--I size up in the tee for an oversized look.

R
Rene R.
Wear it for: Everyday wear
Product Fit: Spot-on
Height: 5'1" to 5'3"
Usual Size: S
Size Purchased: S
My new favorite top

I LOVE this top! I wear it woth jeans or my favorite casual shorts. It looks great and, quite honestly, it makes me happy!

M
M.H.
Wear it for: Running
Product Fit: Spot-on
Height: 5'4" to 5'6"
Usual Size: XS
Size Purchased: XS

Love this shirt! Fits great and the design is super fun!

A
A C.
Wear it for: Running, Everyday wear
Product Fit: Spot-on
Height: 5'4" to 5'6"
Usual Size: S
Size Purchased: S
Love it

This is one of my new favorite pieces. It’s great for days where it’s too cold for a running crop top or light tank top, but too warm for a full t-shirt or long sleeve shirt. I like that it balances feeling soft, with being breathable. The loose fit helps air flow to keep cool as you heat up during a run. When I ordered I measured myself to see where the hem would hit, but because the shoulder seam sits back farther my measurement was off and it was a bit shorter than I expected. Not an issue, just something to be mindful of. I will likely order another color, as I also like lounging around the house and yard in it.

M
Malia W.
Wear it for: Running
Product Fit: Spot-on
Height: 5'4" to 5'6"
Usual Size: S
Size Purchased: S
Comfortable

This tank has become my new favorite for runs. It is comfortable and fits well.

H
Hanna B.
Wear it for: Running, Hiking, Camping, Everyday wear
Product Fit: Spot-on
Height: 5'4" to 5'6"
Usual Size: M
Size Purchased: M
Great cut and multi-functional

I will be living in this shirt this summer! Whether its casual or active wear, this tank fits the bill. Always looking for a shirt that 1- has a nice, comfy loose feel and 2- isnt too long but also isnt a belly shirt. Perfect perfect perfect