The sports bra is the activewear category with the largest gap between marketing and actual performance, and the one where buying wrong produces the most uncomfortable and potentially harmful consequences. The wrong sports bra for the impact level of a specific activity is not just uncomfortable — it provides insufficient breast support during repeated high-impact movement, which has been associated with long-term ligament damage.
The right sports bra — appropriate support level for the activity, correct size, quality construction — changes training comfort fundamentally. For those currently wearing the wrong support level or an incorrect size, a correctly fitted sports bra is the single piece of activewear that produces the most immediately noticeable improvement.
Low impact. Appropriate for yoga, pilates, walking, and light stretching. Encapsulation or compression providing minimal movement control. Most crop-style bralettes fall into this category.
Medium impact. Appropriate for cycling, hiking, strength training, and dance. Combination of compression and light encapsulation providing meaningful movement reduction without the restriction of high-impact designs.
High impact. Required for running, aerobics, HIIT, and team sports. Full encapsulation (each breast supported individually) or maximum compression designed to minimise movement during vigorous activity. Essential for C cup and above during high-impact activity.
Available at: Lululemon (lululemon.com), in stores
Best for: Those who want the Lululemon fabric quality in a medium-high support format for studio and yoga contexts.
The Lululemon Energy Bra uses their Luon fabric — a cotton-feel technical fabric with four-way stretch and moisture wicking — in a construction that provides medium-high support appropriate for yoga flows, dance fitness, barre, and light running. The longline length provides additional coverage and stays in place during dynamic movement. The removable cups allow customisation of coverage and shape.
For studio-specific activities where the combination of movement support, aesthetic consideration, and Lululemon’s fabric quality matters, the Energy Bra is the brand’s most consistently recommended option.
Available at: Sweaty Betty (sweatybetty.com), in stores, John Lewis
Best for: Those who need genuine high-impact support for running and HIIT, particularly larger cup sizes.
Sweaty Betty’s Ultra Run Bra was developed specifically for high-impact activities with consideration for a wider range of cup sizes than most activewear brands address. The encapsulation design (separate cups rather than a simple compression shelf) provides the individual breast support that high-impact movement genuinely requires, particularly for D cup and above where compression-only designs are inadequate.
The racerback construction distributes weight across the shoulders and prevents the strap slippage that standard sports bra straps can produce during vigorous movement. The moisture management fabric handles the perspiration of high-intensity training without the clammy sensation that less technical fabrics produce.
Available at: Brooks (brooksrunning.com), Runners Need
Best for: Women who run and want a sports bra designed specifically for running biomechanics across multiple cup sizes.
Brooks has invested specifically in sports bra design for runners — the brand’s understanding of running biomechanics, stride cycle dynamics, and the specific support requirements of high-impact repetitive movement translates to sports bra design that addresses running-specific needs. The Dare Crossback is their most versatile option, providing high-impact support in a crossback construction that distributes load effectively.
The fit advice: the brand size does not correspond to standard bra sizing in the way most activewear assumes. Brooks recommends measuring and using their specific size guide rather than assuming equivalence with standard bra sizing.
Available at: Third Love (thirdlove.com)
Best for: Those who want medium-impact support with the comfort priority of the Third Love fit philosophy.
Third Love builds sports bras around the principle that comfort and support aren’t compromised. The half-cup sizes that the brand offers (32AA, 36C½, etc.) address the fit gap that standard sizing creates for bodies that fall between standard measurements. For those who have never found a standard sports bra that fits without either inadequate support or digging straps and uncomfortable band pressure, Third Love’s sizing approach specifically addresses this common problem.
Available at: Adidas (adidas.com), JD Sports, John Lewis, Amazon
Best for: Those who want high-impact support at an accessible price from a brand with consistent sizing.
Adidas’s TLRD Impact sports bra provides genuine high-impact support at a price significantly below the specialist brands. The structured underwire and encapsulation design — unusual at the price point — provides individual breast support appropriate for running and HIIT. The sizing runs consistently to standard lingerie sizing, making online purchasing more reliable than brands with activewear-specific sizing.
Available at: Triumph (triumph.com), John Lewis, ASOS, specialist lingerie retailers
Best for: Those with D cup and above who need genuine high-impact support and find activewear-specific sports bras inadequate.
Triumph is the lingerie brand with the most consistently excellent large-cup sports bra range. The Triaction Cardio uses underwire encapsulation with double-layer cups and a wide, cushioned band that provides the support structure that soft-cup sports bras cannot achieve for high-impact activity in larger cup sizes. The construction standard is lingerie-grade rather than activewear-grade, which produces superior fit consistency.
For those who have given up on activewear sports bras for high-impact activity due to inadequate support in larger sizes, the Triumph Triaction represents the specific solution that specialist lingerie construction provides.
The sports bra that doesn’t fit correctly provides neither the comfort nor the support it’s designed for, regardless of its quality. The band should be firm and sit level — it should not ride up during movement. The straps should provide upward support without digging. There should be no overflow at the sides or cups. The centre front (if applicable) should lie flat against the sternum.
UK fitters at John Lewis lingerie departments, Bravissimo (larger cup specialist), and specialist running retailers provide sports bra fitting that is consistently more useful than self-measurement alone.
Sports bra selection requires matching the support level to the activity impact level — this matters more than brand or price. Lululemon Energy Bra for medium-high studio and yoga support. Sweaty Betty Ultra Run for UK high-impact support with larger cup consideration. Brooks Dare Crossback for running-specific high impact. Third Love for the comfort-support balance with half-cup sizing. Adidas TLRD for accessible high-impact performance. And Triumph Triaction for the larger-cup high-impact requirement that activewear brands underserve. Get fitted before buying for high-impact use — the ten minutes at a specialist retailer produces better results than any size guide.