The right type of activity, at the proper time of the day, produces a cascade of powerful chemicals and hormones that decrease the risk of a multitude of disorders, especially breast cancer. For instance, engaging in activities that elevate your heart rate on a regular basis lowers your risk of breast cancer in eight major ways.

First, it lowers the production of estrogen in your body. Breast cancer is strongly linked to estrogen. The more estrogen your body produces and that you are exposed to from other sources over your lifetime, the higher your risk of breast cancer.

Second, regular vigorous activities have been found to lengthen the menstrual cycle. With each menstrual period, your body produces a surge of estradiol the strongest type of estrogen and the one most linked to breast cancer. The longer your menstrual cycles are, for example, they occur every 30 days instead of every 28 days -- the fewer the number of menstrual periods you will have over your lifetime. The fewer menstrual cycles you have, the lower the amount of estrodiol you will produce, and the lower you risk of breast cancer will be.

Third, when you exercise in the proper amounts, the strength of your immune system is boosted. On the other hand, exercising too little, or too much, weakens your immune defenses. Keeping your immune system strong is important because it is composed of cells that provide your body's main defense against foreign invaders like bacteria, viruses and cancer cells. A robust immune system is crucial for preventing and fighting breast cancer.

Fourth, aerobic exercise regulates blood sugar. Sugar is the preferred food for cancer, so it is best not to eat very much of it. Another important reason to keep your blood sugar from getting too high has to do with the hormone insulin. When you eat sugar, especially simple or refined sugars, your blood sugar zooms up and your pancreas responds by releasing a lot of insulin - the hormone that facilitates sugar getting into your cells. Insulin can cause big problems when it comes to your risk of breast cancer. Women with the highest insulin levels are found to have a 283% increased risk of breast cancer. Insulin is also dangerous for women with breast cancer. Breast cancer cells have insulin receptors on them, and when insulin attaches to them, it makes the cancer cells grow faster.

Fifth, aerobic exercise lowers blood fat and keeps body fat in check. Obesity is thought to cause about 20-30% of all post-menopausal breast cancers. After menopause, your fat cells are the primary site for estrogen production in your body. The more fat cells you have, the more estrogen your body will produce. So keeping your body weight down is a good way to lower your risk of breast cancer.

Sixth, exercise relieves depression. According to researchers at the University of Pennsylvania, women who are depressed have a 400% higher incidence of breast cancer. When you engage in strenuous physical activity, your body releases endorphins and other powerful mood-boosting hormones. These chemical changes are extremely effective at relieving depression. In fact, several studies show that exercise works just as well at improving this condition as most commonly prescribed anti-depressant medications.

Seventh, exercising releases stress. Stress has been linked to 90% of all illness according to the National Institute of Health. Research shows that women under severe stress, or that have recently suffered a major stress, like death of a loved one, or loss of a job, are much more prone to developing breast cancer.

Finally, regular exercise has been found to lower IGF-1 or insulin-like growth factor. Keeping the amount that our body produces of this naturally occurring growth factor low is crucially important, because it is the most powerful stimulator of breast cancer known. It is also imperative to be aware that excess amounts of this dangerous growth factor can get into our bodies from consuming dairy products from cows that have been injected with growth hormones. Since most of the cows on conventional American farms are given growth hormones, the only way to avoid ingesting dangerous amounts of IGF-1 is to either not eat dairy products, or to consume only those that are low-fat and have been organically produced.

All of these breast cancer risk-lowering benefits of exercise add up to a lot of protection. Research shows that if you exercised regularly during your teen years, your risk of breast cancer will be 30% lower for the rest of your life. But it is never too late to begin exercising. If you start regularly participating in invigorating movements as an adult and keep it up, you can drop your risk of breast cancer by 30-50%.