Between Sizes in Activewear? How to Decide

Short answer: size up for structured, low-stretch fabrics and rigid waistbands, and stay true to size or size down for high-stretch knits above 20% spandex or elastane. The deciding factor isn't your weight or the label — it's how much give the specific fabric has and which body area the garment needs to hold.

Why Being Between Sizes Happens So Often in Activewear

Activewear sits closer to the body than everyday clothing, so a half-inch difference that would go unnoticed in jeans becomes obvious in a legging or sports bra. Brands also cut for an average proportion — waist-to-hip ratio, torso length — that doesn't match everyone, which is why your waist can measure a Medium while your hips measure a Large in the same size chart. This isn't a flaw in your body; it's a limitation of any standardized chart.

The Fabric Rule: Stretch Percentage Decides More Than the Label

Check the spandex or elastane percentage on the product page before deciding. A legging like the Women's Solid High Rise Leggings, built from 75% nylon and 25% spandex at 220 g/m², has enough stretch to comfortably absorb a between-size decision either direction. A more structured piece like the Women's Criss-Cross Band Sports Bra, with an 80% polyester/20% elastane outer at 250 g/m² layered over a firmer inner panel, has much less give — size up if you're between bra sizes on this style, since a tight band will dig in within twenty minutes of training.

Garment-by-Garment: Where to Size Up vs Down

Using Drawstrings and Adjustable Features to Bridge the Gap

Garments with a drawstring or adjustable waistband give you a built-in buffer. The Men's Drawstring Shorts, made from 77% nylon and 23% spandex at 165 g/m², can cinch down significantly, so sizing up is the safer bet if you're between two waist sizes — you can always tighten the string, but you can't loosen a waistband that's already too small. The same logic applies to the Women's Quarter-Zip Yoga Pullover, where a half-zip neckline adds flexibility a crewneck wouldn't.

What to Do When Top and Bottom Sizes Don't Match

It's common to need a Medium top and a Large bottom, or vice versa. Buy each piece by its own chart rather than forcing a matched size across an entire outfit — HIVOLT sells tops and bottoms separately for exactly this reason. Pair a well-fitted Women's Topstitching Yoga Tank Top with leggings sized to your hip measurement rather than your bust size; nothing about mismatched top/bottom sizing looks or performs worse than forcing one number across your whole body.

When to Just Order Both Sizes

For a piece you'll wear constantly — a daily training legging or your go-to sports bra — it's worth ordering both sizes once, wearing each through a real workout, and returning the one that doesn't hold up. This costs a few extra days but saves you from re-buying the same style twice. Browse bottoms or women's activewear to compare stretch percentages across styles before you order.

FAQ

Should I size up or down for leggings if I'm between sizes?

Stay with your charted size if the fabric has 20% or more spandex or elastane, since that much stretch absorbs a half-size gap without changing how the waistband sits. Size up only if the fabric listed is under 15% stretch fiber.

How do I decide sizing for a sports bra I'm unsure about?

Size up on structured or multi-layer bras and prioritize band comfort over cup snugness, since a tight band causes more discomfort over a training session than a slightly loose cup. You can always tighten adjustable straps after the fact.

Is it normal to wear different sizes in tops and bottoms?

Yes, it's completely normal and expected, since chest, waist, and hip proportions rarely match a single size chart's ratio exactly. Buy each garment against its own specific measurement rather than one blanket size.

What if I size up and the garment ends up too loose?

Look for adjustable features like drawstrings, ties, or adjustable straps that let a slightly larger size cinch down; if there's no adjustment and it's genuinely too loose, exchange for your charted size instead of the size up.

Next, see our breakdowns on what actually holds during high-impact running, the squat test for checking leggings, and why leggings fall down and how to fix it.