How many times have you started a high impact segment of your workout and ended up crossing your arms over your chest to stop the bounce?! It doesn’t matter if you are small or large chested…it happens because we are either wearing a regular bra or wearing a sports bra that does not fit properly. Breasts have no substantial anatomical support, just some connective tissue and ligaments to hold them in place. This substandard lack of support causes them to move relative to the chest wall, especially during running or jumping activities, which may lead to soreness and/or pain.
Breast movement during physical activity is a combination of how much the breast are displaced (large-breasted women will have more displacement than small- breasted women) and the number of times the breast ‘bounce’. The number of times the breasts bounce depends on the length of the exercise session…so if you run at a cadence of approximately 150 steps per minute, your breasts can bounce approximately 9,000 times during one hour of running! Excessive breast motion (up, down, or even a figure eight) has been associated with exercise induced breast pain which can affect your exercise performance or may even stop you from participating in physical activity all together.
Sports bras have come a long way in design since the first ‘Jogbra’ (~1977) which was two jock straps sewn together by a costume designer for an avid runner (Schuster, K., 1979). They are designed to reduce the continuous and repetitive motion of the breasts during activity that can result in soreness, pain and possible sagging of the tissue. Research has shown breast displacement decreases as the level of support increases and as displacement decreases breast pain also decreases (Nolte et al., 2016).
There are three common types of sports bras that are designed to limit breast displacement, 1) crop tops, 2) encapsulation sports bras, and 3) hybrid sports bras. Crops tops are comprised of strong elastic material that limit breast displacement by compressing the breasts as a single unit against the chest wall. Encapsulation sports bras work by enclosing each breast in a structured cup which helps to elevate and support. Hybrid sports bras combine the features of both crop tops and encapsulation sports bras by having two separate cups and an external layer that compresses the breasts against the chest wall. Sports bras that provide encapsulation have been found to be superior to crop tops in limiting vertical breast displacement, a better choice for large- breasted women.
While a sports bra needs to provide the appropriate support, it also needs to be comfortable! When choosing your next sports bra keep in mind the following design features to be sure you are getting support as well as comfort.
Adapted from McGhee and Steele (2020)
References Mcghee, D.E. and J.R. Steele. Biomechanics of breast support for active women. Exerc. Sport Sci. Rev., Vol. 48, No. 3, pp. 99–109, 2020.
Nolte K, Burgoyne S, Nolte H, et al. The effectiveness of a range of sports bras in reducing breast displacement during treadmill running and two- step star jumping. J. Sports Med. Phys. Fitness. 2016; 56(11):1311–7.
Schuster K. Equipment update: jogging bras hit the streets. Phys. Sportsmed. 1979; 7(4):125–8.