Butter yellow athleisure is all I want to wear in the heat: 9 picks that prove it’s the it shade of the summer

It’s official: butter yellow has been hailed as the most elevated way to wear the sunniest shade on the colour wheel - in fact, Google searches for butter yellow have seen a huge spike in 2025. The trending colour has seeped its way into our spring fashion and even our manicure inspiration boards, so it’s only natural that we would want to incorporate it into our best gym wear too. 

Here at MC UK, we’re strong advocates for thoroughly testing the products we recommend - because the last thing we’d want is to make you spend money on something we didn’t know actually worked.

Now, obviously we can’t have an entire wardrobe filled with butter yellow athleisure, that would simply be unsustainable, but luckily loads of our tried and tested fit kit also comes in the trending hue. So here’s our roundup of the best butter yellow activewear - from leggings and workout tops to cycling shorts and unitards - that we’ve tried and love ourselves.

I’m Valeza, Marie Claire UK’s Junior Shopping Editor, and probably one of the strongest advocates for wearing butter yellow that I know. I’m seriously obsessed. Why? Aside from being on-trend and surprisingly easy to style, the hue simply makes me feel happy whenever I put it on - and we could all do with some extra sunshine in our lives, right?

In my bid to bring my favourite summer shade to the MC UK Health page, I also asked Ally Head, our Senior Health Editor, and Dionne Brighton, our Health Writer, for their top butter yellow fit kit picks. Ally is team MC’s resident marathon runner and loves a high-impact workout, and like me, Dionne loves to experiment with all sorts of exercises - Pilates and weight training in particular. Together, we have all tried countless items of athleisure in the name of journalism, so you can rest assured that everything included in this article has been thoroughly squat and sweat-tested prior to your purchase. You are very welcome.

So if you think your workout wardrobe is due a sunny upgrade, keep scrolling to shop the best butter yellow athleisure for yourself. 

Best butter yellow activewear: Quick shopping links

• Best butter yellow workout top: £10.50 at adidas (was £28, save 63%)
• Best butter yellow unitard: £88 at Free People
• Best butter yellow long sleeved top: £48 at Oner Active
• Best butter yellow sports bra: £34 at Adanola
• Best butter yellow shorts: £75 at Vuori
• Best butter yellow sweatshirt: £60 at Adanola

What did we look for when testing?

Like all of the best gym wear we’ve tested, our butter yellow athleisure picks had to tick several boxes to make the cut:

• Fit: were they comfortable and stretchy? Did they have a flattering fit?
• Material: did they sweat-wick well and pass the squat test? Did they move with us throughout our workouts?
• Performance: were they better suited to high or low-impact workouts?
• Price: would we get our cost per wear?
• Colour: was it a citrusy hue or more of a creamy yellow? Both were welcome: brighter yellows pair well with a colour-clash workout outfit, while softer tones work well with neutrals, But overall, these pieces had to have that ‘buttery’ element to make them fit with the trend.

1. Best butter yellow sports bra

This bra actually inspired this round up - the perfect sunshine shade of yellow, sure to brighten up any summer workout. Other need to knows about Adanola kit - it's seriously sweat wicking, comfortable, and easy to throw on, too. It's easily team MC UK's most recommended sportswear brand thanks to the high performance and low price point. If you're a fan of the look, you can even pair it with the matching tennis skirt for a full butter ensemble.

2. Best butter yellow unitard

How stunning is the shade of this running unitard from FP movement (aptly named the 'runsie')? Ally owns it in a few colours and swears by it as an easy throw-on-and-go running outfit. She loves how soft and supportive it is and the fact that it looks incredibly chic too. Do keep in mind, though, that it's best to wear an extra sports bra underneath for high-impact sports.

3. Best butter yellow cycling shorts

When it comes to cycling shorts, I'm super picky: they need to be comfortable yet still supportive and not dig into my thighs - these shorts tick every box, and now come in a chic yellow shade to boot. I own them in several colours and love them for lower-impact sports like Pilates or simply running errands. At well under £15, they're easily the most affordable product in this list, and I'm super impressed by the quality, considering their price. But be warned, they sell out extremely fast.

4. Best butter yellow workout top

Ally raves about this adidas workout top, so imagine my delight when I saw it was available in butter yellow and with an impressive discount. She's a fan of how the airy mesh detail makes it super breathable and great for running and weight training alike, plus the high neck design offers extra support and coverage.

5. Best butter yellow long sleeve

Another brand that we can't get enough of is Oner Active. It offers impeccable quality for a reasonable price tag, with trendy yet timeless pieces that sweat wick and provide lasting comfort. This long sleeve is no exception, and I can attest to how well this fabric performs during lengthy workouts like my Reformer Pilates classes.

6. Best butter yellow oversized gym T-shirt

Multiple people on the MC team own and love Adanola oversized tees, and this butter yellow shade is simply perfect for summer. Dionne loves the heavyweight cotton, which washes well and makes the T-shirt feel far more expensive than it actually is, but beware, it might not be the best material for hot, sweaty workouts.

7. Best butter yellow everyday shorts

Vuori activewear is easily some of the most comfortable in my collection, so these shorts are ideal if you're after something loose and breathable for summer workouts. The moisture-wicking material also offers four-way stretch and the fabric doesn't wrinkle, meaning they're ideal for taking travelling too. Due to the roomy design they're slightly more leisure-appropriate than workout ready, but they can certainly work for low impact exercises.

8. Best butter yellow gym bag

Don't underestimate the power of one of the best gym bags. They're essential if you're a regular gym-goer, especially if you head straight from your workouts to the office. Sweaty Betty bags are always high quality, and this spacious tote has ample room for everything you need to cart around with you. And who can resist this stylish butter yellow and brown combo?

9. Best butter yellow sweatshirt

This sweatshirt comes in the same butter yellow shade as the oversized tee above, and I'm obsessed. I imagine it pairing really well with chocolate brown leggings and some off-white trainers. I own a few Adanola hoodies and sweatshirts, and nothing beats them for running from brunch to barre - each selection is thick, washes well and feels far more expensive than it actually is.