The Best Sports Bras for Running

No matter your breast size, wearing a sports bra is essential when doing high-intensity exercise like running. Research has found that unsupported breasts will move up and down as much as 12 cm during activities like running or jumping. That’s because there aren’t any muscles within the breasts – they’re mostly a collection of fat and tissue held by two objectively weak structures: the skin and ligaments known as Cooper’s ligaments. This allows the breasts to move in a figure-eight motion, swinging up and down, forward and backward, and side to side. 

The force of high-intensity exercises, like running, can cause your breasts to move more vigorously. When the breasts aren’t well-supported, it results in two primary issues: breast pain and stretching of the skin and ligaments (which can cause sagging). A 2012 survey of the London Marathon found that of the 1,285 female runners studied, 32% experienced mastalgia (breast pain), and 75% of those runners had issues with bra fit – highlighting the importance of wearing a well-fitting, high-impact sports bra when running. 

Not wearing a sports bra when running can also affect your performance. Research shows that wearing an ill-fitting sports bra or not wearing a sports bra at all slows down the range of motion, averaging a loss of 4 cm in stride length. Thus, wearing the right sports bra can improve performance and reduce distractions by minimising breast movement. 

In addition to preventing breast pain, supporting overall breast health, and improving performance, sports bras also help improve your posture. Sports bras act as temporary posture correctors, pushing back the shoulders, so you stand taller and more confident

Sports bras are divided into three impact levels: low, medium, and high. When running, you should wear a supportive sports bra that will hold you in place. When choosing a sports bra you should consider your breast size, and the impact level of the exercise you’ll be doing. To help make things a little easier, we’ve explained the impact levels below.

The most important feature of any sports bra should be the level of support it provides you during exercise. As we’ve mentioned, sports bras are designed for different levels of activity and impact, so you want to choose a bra that works for your cup size and workout intensity to control breast movement effectively. You want your sports bra to be snug to provide adequate support but not too snug where it causes discomfort and distraction.

To ensure you choose a good sports bra for running, we recommend a sports bra that is medium to high impact, depending on your cup size. A high-impact sports bra is critical if your breasts are on the larger side. Smaller and medium size busts will benefit from the support of a medium-impact bra. But at the end of the day, choose a support level that feels best for you.

The best sports bras for running have adjustable straps. Why? Adjustable bra straps – just like in your regular everyday bra – improve the level of support. If you opt for a style without adjustable straps, you’re relying on the elastic in the strap to support your bust, and once this elastic stretches out, your sports bra won’t provide the support you need. A sports bra with adjustable straps should last longer in your collection since you can tighten it as the straps start to loosen.

The closure of your sports bra is also important. You may already be familiar with sports bras that are a bralette/pullover style. It’s a suitable style for those with smaller breasts, but it isn’t sufficient (or efficient) for larger breasts. If you have a large bust, look for a sports bra with a clasp or closure that allows for easy on and off. A hook-and-eye closure will allow you to tighten the back, providing more support and security during your workout.