When you have a goal in mind, nothing’s going to stop you. And this is why it’s so important to know how to choose a sports bra. With the right performancewear on, you can train harder, without distraction, and with complete confidence. 

At Under Armour, we build the world’s most technically advanced sports bras for women and girls. 

In this guide, we walk you through the essentials to help you choose the right gear for your sport and training intensity. You’ll also learn how to measure sports bra size and how they should fit. 

A sports bra is, arguably, your most important piece of performancewear. When you run, jump, stretch or change directions, your breasts move too. 

Without adequate support, intense movement can strain or even damage the connective tissues (known as Cooper’s ligaments) that support your breasts. Inadequate support can also affect your posture, and leave your back and neck sore. 

Wearing a fitness bras can:

• Prevent ligament damage

• Support your breasts

• Reduce distracting movement

• Eliminate soreness after exercise

• Reduce pain in your back, shoulders and neck

• Help you maintain an upright posture

The best sports bras give you more. At Under Armour, we use breathable, sweat wicking fabrics so they stay dry, and don’t chafe. They’re built to be easy on and off. And we use super soft performance fabric that’s made to last. 

Sports bras fall into three categories: high impact, mid impact and low impact. 

This is mainly about the intensity of the activity - for high impact sports (like running, football or HIIT classes) you want a more supportive bra. For lower impact sports (like yoga, golf or hiking) you don’t need quite as much compression. 

But it’s also about your body, and the size and shape of your breasts. If you have larger breasts, you’ll benefit from more support - even for lower impact exercise. 

Thinking about the intensity of your activity can really help when deciding how to choose a sports bra. 

A high impact sports bra provides serious support when you’re grinding hard. They’re built for high intensity exercise that involves running, jumping and rapid movement of any kind (squats, lunges, mountain climbers etc.).

Pick up a high impact sports bra, and you’ll find the following kinds of features:

• Encapsulation: They’ll usually have a defined cup for each breast. That helps reduce side to side or up and down movement. 

• High compression: The material will feel supportive and firm and will be built with robust fabrics. 

• Adjustable straps: These let you find the perfect fit so they don’t slide off or dig in. They also help with posture and help you avoid back and shoulder pain. The straps tend to be broader than in lower impact bras to rescue impact too. 

• Wide bottom band: A wider bottom band gives you more support and structure. 

• Sweat wicking and breathable: These bras are built for the time of sweat. Technical fabrics, mesh panels and quick dry materials keep them comfortable. 

A medium impact sports bra will fit snug and give plenty of support, but with less compression than a high impact bra. They’re engineered for things like weight lifting, cycling, elliptical machines, hiking, or using the rowing machine. Basically, any activity where your heart rate goes up, but without loads of running and jumping. 

You’ll find the following kinds of features in medium impact sports bras:

• Medium compression: They can have cups or they may be cupless. Either way, they use compression fabrics to hold your breasts firm to your chest. 

• Natural movement: They will allow for some flex, letting you move without restriction. 

• Lighter weight: They tend to be a little lighter than high impact sports bras. 

Sweat wicking and breathable: You’re still going to sweat and get hot, so they’re built with breathable, fast-drying fabrics. 

These sports bras will reduce movement and keep you feeling supported during low impact exercise - things like golf, speed walking, yoga and Pilates, using weight machines, or riding the exercise bike. 

You can tell a low impact sports bra by the following kinds of features:

• Usually cupless: They typically use compression fabrics to hold your breasts in place. 

• Stretch: You’ll find soft knit fabrics and four-way stretch material that allows for natural movement. 

• Straps: They often use skinny, elasticated straps that hold in place. 

• Sweat wicking: They dry fast, wick sweat and should provide plenty of ventilation. 

This is gear that’s built for working hard in. So it’s essential it fits well, and gives support in the right places. Here’s how to fit a sports bra. 

1. Find your band size

Stand in front of a mirror wearing a non-padded bra. Using a soft measuring tape, bring the tape across your back at band level, under each arm, around the front and measure just above the bust (a good guide is where your bra strap meets the bra).

2. Find your bust size

Measure completely around the fullest part of the bust being careful that the tape isn’t too tight and binding or too loose and pulled away from the body. With the tape in position, take a breath in and out, allowing it to slide to its most comfortable fit. 

Now, use the following size chart to find the right sports bra for you:

Size in Inches

Size in Inches

Knowing how to choose a sports bra can help you select gear that lets you train more confidently, comfortably, and with better concentration. Under Armour sports bras give you the most technically advanced, long-lasting and reliable performancewear, helping you push your limits and smash your goals. 

Ready to train? Discover our complete range of high, mid and low-impact sports bras for women and girls.