Which Activewear Brands Run Small, Large or True to Size? Our Fit Notes in One Table

Size charts tell you a brand's measurements. They do not tell you whether a legging with firm compression feels a size smaller than its chart, or whether a relaxed tee is cut to be worn loose. That is the question our reviews answer one product at a time, and this page collects every one of those answers in one place.

We went through all of our guides, pulled every statement about how a product or brand fits, and put them in the tables below with a link to the guide each note comes from. Nothing here is new: each row repeats what the linked guide already says, compiled in September 2026. Where a note comes from the brand's own listing rather than our testing, the row says so. Where two of our guides disagree, we show both rather than pick one.

How to Read the Tables

• Runs small means our guide (or the brand) says to size up, at least when you are between sizes.
• True to size means your usual size on the brand's chart is the right one.
• Runs large means the cut is generous and the smaller size is the safer pick between sizes.
• Fitted means the cut sits close (slim, athletic or narrow) without the brand running small; the note says when to go up.
• Relaxed cut means the piece is designed to be worn loose; size down if you want it fitted.
• Guides differ means two of our guides say different things; the note explains both.

A fit note is not a replacement for the chart. Measure first, then use the note to decide which way to go when you land between two sizes.

Leggings and Yoga Pants

Sports Bras

Tops, Tanks and Tees

Hoodies, Jackets and Joggers

Shoes, Socks and Accessories

Where Our Guides Disagree

Five products get different fit notes in different guides. The notes were written at different times, against different comparison brands, and sometimes by different testers, so we show the disagreement instead of hiding it.

CRZ YOGA Butterluxe. Our CRZ YOGA vs Lululemon and Butterluxe vs Butterlift comparisons found it true to size, and our Lululemon dupes guide says CRZ runs closest to true Lululemon sizing. Our best workout leggings, yoga pants for women and petite yoga pants guides say it runs slightly small next to Lululemon and suggest going up if you are between sizes. The practical reading: take your usual size, and if you are between two sizes, go up for a relaxed fit or down for a snugger one.

ODODOS leggings. Best workout leggings says slightly small; Lululemon dupes on Amazon says generous through the hips. If your hips are your widest measurement, your usual size is likely fine; otherwise size up between sizes.

Gymshark seamless leggings. Our squat-proof test found the High-Waisted Seamless true to size with a body-contouring fit; our Gymshark vs Lululemon comparison says Gymshark has historically run small and recommends sizing up in seamless pieces if you prefer less compression. Both can be true: take your usual size for a contoured fit, one up for a softer one.

Under Armour Tech 2.0 tee. Under Armour's listing says it runs a little small, and our sweat-proof shirts guide passes that on. Our Nike vs Under Armour comparison calls UA sizing true to slightly generous overall and suggests the smaller size if you are between two, and our men's yoga clothes guide describes the Tech 2.0 as a classic, loose-enough cut.

Alo Accolade hoodie. It is oversized by design. Our Alo fabrics and sizing guide says order your true size and only size down for a fitted hoodie; our Alo sets and fall layering guides recommend a size up for the boxy look over a fitted set. Your true size is already relaxed; a size up is a styling choice.

Patterns Worth Knowing

Compression runs small. Almost every compression product in the tables, from Under Armour HeatGear and Fly-By to Alo Airlift and TYR's speedsuit, gets a "size up" note. Our compression wear guide puts the rule simply: if you are between sizes, or want compression that is firm but not restrictive, size up.

Soft and relaxed fabrics run the other way. Alo Seamless, Beyond Yoga and NELEUS tees get "size down" or "never size up" notes, because the fabric relaxes or the cut is already loose.

Sizing up does not fix a sheer legging. Our squat-proof leggings guide is blunt about this: a bigger size adds loose fabric at the knee and waist without adding density, and the waistband slides during squats. Only size up in a brand known to run small. If a legging is see-through, you need a thicker fabric, not a bigger one; our activewear fabric chart lists what the leggings we cover are made of.

Bras run small. Three Nike bras and Gymshark's Seamless Racerback run small, two of them specifically in the band. Our sports bra size guide explains sister sizing if the band fits and the cup does not.

How We Compiled This

We searched every guide on the site for fit and sizing statements ("runs small", "true to size", "size up", "size down" and similar) and kept only statements tied to a named product or brand. Each row links to the guide it comes from; where a note repeats the brand's own listing rather than our testing, the row says so. General advice that applies to any brand (measure your knee for sleeves, measure your upper arm for arm sleeves) is left out. We will update the tables when a guide's fit note changes.

Frequently Asked Questions

Does Lululemon run small?

No. Our guides find Lululemon's Align and Wunder Train true to size across the 0 to 20 range. Take your usual size in Align and do not size down; the fabric is thin enough that stretching it past its design shortens its life. Wunder Train can feel snug if you are between sizes.

Does Alo Yoga run small?

It depends on the fabric. Airlift runs about half a size small, and Airbrush leggings run half a size small too, so size up in both if you are between sizes. Alosoft and Micro Waffle run true, and Seamless runs true to roomy, so never size up in Seamless.

Do CRZ YOGA leggings run true to size?

Mostly. Our head-to-head comparisons found Butterluxe true to size, while two roundups found it slightly small next to Lululemon. Take your usual size; between sizes, go up for a relaxed fit or down for a snugger one. Butterlift, with firmer compression, can feel snugger than Butterluxe.

Does Gymshark run small?

Gymshark's seamless pieces run small in our brand comparison, and the women's Fitted Seamless tank, Seamless Racerback bra and men's Arrival tank all get "size up" notes. The Vital Sculpt bra ran true to size, and the men's line runs closer to true.

Does Nike run small?

Nike gym wear runs true to size with a slim, athletic cut, but several specific pieces run small: the Swoosh High Support bra (about a half size), the Indy and Swoosh Medium bras in the band, the Dri-FIT Legend tee, the One 7/8 leggings and the Pro arm sleeves.

Does Under Armour run small or large?

Under Armour tees and everyday gym wear run true to slightly generous in our comparison, but UA's compression lines (HeatGear leggings, Fly-By capris, the HeatGear Scoop Tank) run small, and UA's own listing says the Tech 2.0 tee runs a little small.

Should I size up for compression wear?

If you are between sizes, yes. Every compression product in our tables gets a size-up note, and our compression wear guide recommends sizing up if you want compression that is firm but not restrictive.

The Bottom Line

Size up in compression and in the pieces the tables mark small, especially Nike's Swoosh High Support bra, Alo Airlift, Gymshark seamless and Alphalete. Take your usual size in Lululemon, Vuori, Sunzel and most Under Armour tees. Size down, or at least never up, in soft relaxed pieces like Alo Seamless and Beyond Yoga. And where our guides disagree, the note tells you which way each choice pushes the fit.