Episode 23 | Ask the Expert | Guest: Elinor East – Physiotherapist and Co-founder, Movement Perfected
It’s not a topic that comes up in most physiotherapy consultations. But for Elinor East, a musculoskeletal physiotherapist with 12 years of clinical experience and co-founder of Movement Perfected in London, bra fitting has become an integral part of how she approaches postural pain in women – and the results speak for themselves.
In this episode of the London Bridge Sports Medicine podcast, Elinor joins Lucie to explore the anatomy behind breast support, the research on how bras affect sporting performance, and the practical checklist every woman can use to assess whether her bra actually fits.
How breast anatomy makes support so important
Breasts have no muscle tissue. They sit on the pectoral muscles of the chest wall and are held in place only by the surrounding skin and Cooper’s ligaments – which are very small and thin. The average woman carries around 900 grams of breast tissue. That weight, unsupported or poorly supported, has to go somewhere – and it is borne by the posture and the muscles of the neck, shoulders, and back.
Elinor’s interest in breast health developed during the pandemic, when she noticed a significant increase in postural neck and shoulder pain among her female patients. Many had stopped wearing bras while working from home – a comfort choice that, combined with prolonged sitting in poor positions without proper desk setups, was loading the upper body in ways it wasn’t designed to manage for hours at a time.
The link between bra fit and pain
The most visible sign of a poorly fitting bra is what Elinor calls “train track lines” – deep indentation marks left by bra straps on the shoulders. When a bra is too small in the cup or too large in the band, the straps take on the work of supporting the breast weight. Those straps press down on the muscles and nerves of the neck and shoulder, while simultaneously pulling the chest weight forward and rounding the shoulders.
The result is a pattern Elinor sees repeatedly in clinic: the posterior chain – the muscles of the upper and mid back – either works excessively hard to counterbalance the forward pull, or switches off entirely in a sedentary patient, contributing to chronic neck, shoulder, and back pain.
Most patients, she notes, are already aware their bra doesn’t fit well. They just haven’t connected that to the pain they’re presenting with. “They say, I feel like I need to pull it down, but I haven’t got around to getting it sorted.” Having a physiotherapist make the connection in a clinical setting – someone they trust, who can frame it within the context of their pain – removes much of the awkwardness.
The impact on sport and exercise
The clinical evidence for breast support during exercise is substantial – and comes largely from the Breast Research Group at Portsmouth University, which has been studying this area for nearly 20 years.
Key findings include:
- At a moderate running pace, breasts can move up to 14 centimetres per stride when unsupported. Over a 10K or marathon, that cumulative movement creates significant muscular load.
- Running without adequate support increases activation in the pectorals, anterior and medial deltoid – muscles that should not be working hard during a run. This wastes energy that could be directed into forward propulsion.
- Trunk and arm movement also increases with poor breast support, further reducing efficiency per kilometre.
- Women running with low support reported a higher rate of perceived exertion at every kilometre compared to those in a high-support sports bra – feeling the effort as harder even at the same pace.
- A rounded posture from inadequate support also reduces lung capacity: less thoracic extension means less room for the chest to expand and fill with air.
Perhaps the most striking statistic Elinor cites: 51% of female athletes at the Tokyo Olympics reported breast pain, chafing, and musculoskeletal discomfort linked to inadequate bra support. These are elite athletes – and they were still underserved.
Beyond performance, inadequate breast support is a genuine barrier to exercise for many women – particularly those with larger cup sizes who feel self-conscious about breast movement, or who resort to wearing two bras simultaneously. Elinor has seen patients who only exercise at night, or who wear baggy clothing to disguise themselves, or who simply don’t exercise at all. “The last thing you want is for them to stop exercising and stop going to the gym – that leads to lack of motivation, weight gain, and all the other factors involved in not exercising.”
Types of sports bra: which one do you need?
Compression bras
The traditional crop-top style sports bra. A single layer of stretchy material that compresses the breast tissue against the chest wall. Available in small/medium/large sizing, comfortable, and good for lower-impact activities (yoga, Pilates, walking). Generally better suited to smaller cup sizes (A–C). Because the underband is stretchy, it provides less support than an encapsulation bra – making it less suitable for high-impact sport in larger cup sizes.
Encapsulation bras
Each breast is held separately in its own cup, usually with underwiring. Sized by specific chest and cup measurements (e.g. 32B) rather than small/medium/large, so fit is more precise. The underwire, when correctly fitted, creates a boundary around the breast tissue and provides significantly more support. This is the recommended type for higher-impact sport and for larger cup sizes. A racerback design and higher neckline add further support.
Hybrid bras
Many brands now produce bras that combine compression and encapsulation features. The research group at Portsmouth University has worked with several major sporting brands on design, so the options have improved considerably. As with trainers, fit varies significantly between brands – and even between styles within the same brand. Elinor recommends being open to trying different sizes and styles rather than assuming a fixed size.
How to tell if your bra fits: a practical checklist
Elinor runs through five key checks:
- The underband – this provides around 90% of the bra’s support. It should feel like a firm shelf, sit level across the chest wall (not riding up the back), and have no more than 5cm of give when you lift your arms above your head or jump. If you’re constantly pulling it down, it’s too small.
- The straps – adjustable and should be set so you can fit one finger underneath, but no more. Note that straps can be adjusted independently if one breast sits slightly differently to the other – symmetry is not required.
- The centre front – in an encapsulation bra, the centre panel between the cups should lie flush against the sternum. A gap means the cup is too small and the breast tissue is pushing outwards.
- The cups – no tissue should spill over the top, sides, or underarm. Any spillage means you need a larger cup. Equally, wrinkling in the cup material means it’s too large.
- The underwire (if applicable) – should sit flush all the way around the breast tissue, without pressing on the breast itself or the chest wall. Underwire sitting on breast tissue is a sign the cup is too small.
The best test: put it on and move. Jump up and down, raise your arms, twist. If everything stays in place and nothing pinches, digs, or rides up, you’re in the right bra.
The bottom line
Breast support is a musculoskeletal issue – and one that has been chronically under-discussed in both clinical and sporting contexts. The right bra does not just affect comfort; it affects posture, pain, breathing, exercise performance, and confidence. The wrong bra, worn for years, can be a significant and easily overlooked contributor to neck, shoulder, and back pain.
“If I can change just one person to wear the right bra,” says Elinor, “that’s a big win.” Given the evidence, it’s hard to argue with that.
Elinor East is a Physiotherapist and Co-founder of Movement Perfected, a musculoskeletal physiotherapy practice with clinics in Marylebone and Moorgate, London. She offers bra fitting as a clinical service alongside postural assessment and musculoskeletal rehabilitation. Find out more at movementperfected.com.
To book an appointment with the LBSM team, visit lbsm.co.uk/booking
Listen to the full episode below ↓
