According to the latest research carried out by the Shock Absorber Sports Institute (SASI) at Portsmouth University, millions of women worldwide are not supporting their breasts properly. Could you be one of them?

Learn how you can protect your assets by investing in proper support.

Why wear a sports bra?

The average breast weighs between 250 and 300g, and any unsupported movement – such as running – causes three-dimensional movement: up-down, in-out, and side-to-side.

This can result in discomfort, chafing and strain on the breasts’ supportive tissue – the Coopers ligaments – which in turn can eventually lead to sagging.

In fact, research also shows that on average, a woman’s breast moves 9.08cm with every stride when running.

What’s my size?

“There’s no magic formula to finding out which bra size will fit you best,” says Shock Absorber’s Julia Nolan. If you have never worn a sports bra before, start with your usual bra size but be open to trying on different sizes before you find the perfect fit.

“First of all, ensure that the back band is at the same level all the way round. If it rides up, then it’s too big,” suggests Nolan. Your sports bra should fit snugly, but not be so tight that you can’t breathe.

“You should be able to get no more than one finger under the band or in the cup, and the material should not pucker at all,” says Selaine Messem, founder of an online sports bra shop.

Encapsulation bras have two cups like a normal bra, but with extra support. Compression bras, on the other hand, press your breasts against your chest, and are usually pulled on over your head. If you’re opting for the former style, then make sure the centrepiece lies flat against the breastbone.

What shape of bra best suits my breasts?

Trial and error is the best way to discover which brand, model and size fits your breasts best. Most retailers should be able to suggest a selection of bras that, based on your body shape and level of activity, will suit you best.

Don’t forget though, that the shape of your bra will have an impact on how effective it is in reducing movement while running. “As with running shoes, many women stick with the same model of bra once they’ve found the one that works best for them,” says Messem.

What level of support do I need?

Different bras offer different levels of support. The type you need will depend on your cup size and the type of exercise you do.

RELATED: WATCH: How To Find The Perfect Sports Bra

Low-impact sports bras, used for stretching or walking, are often cut like a crop-top and are, on the whole, made from thinner material. High-impact bras (for running) generally use less stretchy material, include supportive seams and overlays and are sometimes even underwired.

Running causes a large amount of breast movement compared with many other sports. “The level of support required does vary according to bra size, but whatever size you are we would recommend opting for maximum support,” says Messem.

I’m smaller-/larger-chested than average, what options do I have?

Smaller-chested women may feel most comfortable wearing a compression sports bra. However,warns Messem, there is research to suggest that a properly structured encapsulation bra – which cups each breast individually – is more likely to give good support than a compression bra.

For larger cup sizes, encapsulating sports bras are definitely recommended; although some bras offer a combination of both encapsulation and compression.

What if I am pregnant or breastfeeding?

During pregnancy or when breastfeeding you will need the maximum support available. In addition, your bust size will change throughout your pregnancy, so consider buying an adjustable bra to avoid frequent replacements.

Some women find that wearing a crop top over a sports bra is the only way to stay comfortable when running during pregnancy.

Why has my sports bra started to chafe?

Sports bras usually start to chafe when the elastic has begun to age. It can also occur more frequently on longer-distance runs – this is because of the increased movement of the bra against the skin, due to perspiration.

RELATED: How to Prevent & Treat Chafing

“One solution is to tighten the rear-fastening by one notch before setting off,” suggests Messem. “This can also be a solution if you’ve recently started running (or increased your training) and have lost weight.”

Like running shoes, a new sports bra will also need be worn in, so to avoid any unexpected problems, best not to wear a new bra on race day!

How long does a sports bra last?

“After 30-40 washes most sports bras need replacing. As a rule of thumb you will need three new bras for every one pair of running shoes,” says Messem.

The technical fabric of your sports bra will wear in the washing cycle, and its elasticity will diminish during use. Try not to tumble dry your bra either: the heat will destroy the fabric on your bra and reduce its life.

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