It's causing a storm in a D-cup.

Australian lingerie company Berlei have unveiled an advert that doesn't hold back when it comes to describing what boobs go through when engaged in sport.

“Stop your boobs playing their own game” campaign is to highlight how much pain can be attributed to a lack of protection.

If you saw this advert out of context you might be like:

Head Designer for Berlei Innovation, Adele Kershaw said, "Women are aware of the need for different equipment such as footwear and clothing for different sports, but they need to be aware of the importance of wearing the right sports bra for different sports to prevent this damage."

According to research 40% of women don't wear the correct type of sports bra so to highlight it they have knockers (big balls really) really getting put through their paces. 

Get ready to get an eyeful.