Thanks for the mammaries: Exercise and your breasts

Just as you’ve probably heard all kinds of terms for breasts — jugs, tits, knockers, the girls, funbags, sweater meat — you’ve probably also heard all kinds of horror stories about breasts and exercise.

For example, in the 1980s, women were officially banned from competitive boxing in Ontario. Boxing executives argued that if a woman got hit in the breast, it would cause breast cancer. Indeed, the kindly gentlemen felt so strongly about protecting the ladies’ delicate buzzums that they sent cops to bust up an attempted women’s match. (No word on their efforts to protect testicles.) I’m sure those dudes are big contributors to pink ribbon funds everywhere now.

To understand what effects exercise actually has on breasts, let’s start with the anatomy.

breast anatomy

Cross-sectional view of the breast

Cross-sectional view of the breast

Breasts are composed of both fat and glandular breast tissue. Anatomically, they’re sort of like bunches of grapes in Jello — the grapes are the glands and the Jello is the fat.  As the image shows, the breasts sit on top of the pectoral muscles. There are also lymph glands, which are little nodes of tissue that are part of the immune system, threaded throughout the top and sides of the breast towards the armpit and collarbone.

The breast is supported by connective tissue in the form of Cooper’s ligament, a ligamentous band that holds the breast like a natural bra or sling. This tissue is strong but not invincible. If the breasts have any appreciable weight, the ligaments benefit from a little help in the form of a good bra. (More on this below.)

Men and women actually have the same basic breast structure; it’s just that women’s breasts are more developed and substantial as a result of hormones released during puberty. Men whose hormonal environment contains excess estrogen, such as men taking too much testosterone (which aromatizes into estrogen), or men who are carrying a lot of bodyfat, may experience gynecomastia, or the growth of breast tissue. Men can also sufer from breast cancer, by the way. And they can lactate if given appropriate hormones. (Rather useful, really.)

Hormones do play a role in breast size: folks taking supplemental estrogens may also notice breast growth. You’ll probably notice changes in breast size and texture over the course of your menstrual cycle. And then of course there are the legendary — indeed, epic — pregnancy gazongas.

breasts and body fat

Because much of the breast is body fat, overall body fat levels will play a part in shaping your snoobs. But the relative amount of glandular tissue and body fat composition varies from woman to woman. For example, some women will have larger breasts even if they have lower bodyfat, and other women will have relatively smaller breasts at any level of bodyfat. Women who are genetically more “apple shaped” will have larger breasts, while women who are genetically more “pear shaped” will usually have smaller breasts at the same level of body fat. At my heaviest, I contemplated buying a 38D bra. At 5’0″ and pear shaped, I leave it to you to calculate how big my ass must have been for that to occur.

So, while losing bodyfat is a pretty reliable way to shrink your breasts, genetics will determine just how much you lose. In general, though, it is quite rare to have large breasts at a low level of bodyfat, which is why most swimsuit and fitness models have implants.

If you’re considering a reduction, think about getting your body fat into a healthy or even lean range first through regular activity and good nutrition. This is a much less invasive way of managing the situation.

gravity can get you down

Since the breasts are basically bags of gooshy stuff that aren’t supported by a hard skeleton or a lot of connective tissue, they move a lot and suffer the effects of gravity and breastfeeding. As we age, the natural elasticity of our tissues loses its sproing, and the girls start to head south.

Women who run a lot, and/or women with larger breasts may also experience pain in their upper/mid back and neck as the weight of the breasts pulls their spine forwards. A good sports bra will help counteract this downward force and make things more comfortable. It won’t prevent gravity entirely (hey, gravity’s not just a guideline — it’s the law) but it will ensure your girls go kicking and screaming all the way.

muscle and breasts

As you’ll notice, the breasts sit on top of the chest wall. Thus, it’s a myth that building up the pectoral muscles underneath the breasts will make them perky if they are already sagging.  The visible division of the pec muscles at the top of the ribcage does help to create the illusion of cleavage if you’re lean and lacking it. However, the breast tissue is independent of the muscle beneath it, so you can’t make your breasts bigger (or smaller, depending on which rumours you listen to) by doing any form of chest work. Building muscle mass on the chest, or doing any form of pectoral exercise, will do nothing to affect the shape or size of the breasts themselves.

Do not be dissuaded from doing chest work because someone says your breasts are already big enough, or that pressing exercises will somehow harm your breasts. You’re not going to develop massive pectoral muscles, and you need to work your entire body. The pecs perform an important function of drawing the upper arm across the body. That being said, many women would benefit more from doing more pulling/mid-back work such as wide-grip rows, in order to counteract the forward/downward pull from their breasts.

breast cancer

Like the buzzkills from boxing who assumed that breast cancer was a significant health risk, women may think that breast cancer is a top killer. In fact, your risk of breast cancer is much lower than the less exciting killer: cardiovascular disease. According to the World Health Organization, nearly 1/3 of deaths among women are from some form of CVD. Cancer is an important killer that accounts for around 13% of deaths, but the #1 cancer is lung cancer. 80% of those lung cancer deaths are from smoking.

In other words, it’s good to be safe and sensible about breast cancer. Research shows that a diet high in fruits and vegetables, regular activity, and maintaining a healthy body fat is important. Obesity produces a hormonal environment that is conducive to cancer growth; one reason that breast cancer can be so deadly is that the lymph nodes sit adjacent to the breast tissue and breast fat. You know how one jerkoff neighbour can ruin it for everyone with his car up on blocks and beer cans all over the driveway? Same idea. Just like your atrocious neighbour, the chemicals produced by excessive body fat pee all over everyone’s lawns, and if that lawn next door is a lymph node, that’s big trouble.

We should also be concerned about things like chemical exposure, hormone use, and environmental hormones. Inspect your breasts regularly. But if you have to choose one thing to worry about, focus on your heart before fretting excessively about what’s on top of it.