The capacity of staying physically active and healthy may be linked to breast cancer risk, according to a study published this month by Oxford University Press. The research on rats revealed that inherited fitness could play a significant role in the chances of developing the incurable disease. The findings are opportune to discuss during the breast cancer awarenessw month, which is focused on prevention.

The researchers found that low-fitness rats were four times more likely to develop breast cancer compared with rats born with high fitness.

Prolonged and frequent periods of television viewing, sitting and lying down increase the risk for chronic conditions like cancer, type two diabetes, and cardiovascular disease, according to the National Cancer Institute at the National Institutes of Health. Survival rates are higher for sedentary people compared with individuals engaged in the regular physical activity.

Inherent fitness linked to breast cancer risk
For Breast Cancer Awareness Month, please get tested for any signs of cancer risks. Image Source: The Conversation

Everyone knows that physical activity helps prevent a wide range of diseases and that most fitness people who are diagnosed with chronic conditions have better outcomes. However, the majority of fitness-related studies have not taken into account the role of genetics.

The ability to transport oxygen and nutrients to the muscles is known as aerobic fitness, which has a heritable component, as explained by study author Henry J. Thompson in a report published by Medical Xpress. That could explain why the same amount of exercise produces different results in people engaged in the same training program.

For this study, the team of researchers considered the inherited fitness capacity as a potential link to breast cancer risk. They used rats instead of humans because involving people would have required a risky, large-scale research on individuals with a lifetime of sedentary behavior, which affects health and well-being.

For many generations, the study authors repeated a procedure that consisted of selecting rats with low or high running activity on a treadmill so they could mate with one another based on their activity levels.

In other words, the researchers formed one family of rats that ran the farthest before tiring and another family of animals that tired of running early. This procedure helped them isolate the effects of inherent fitness to ensure that the running activity was a result of the inherited component and not exercise-related.

The team kept the female rats from both groups and exposed them to chemicals designed to trigger the development of breast cancer before they reached sexual maturity. They then monitored the lab rodents to identify the palpable and small tumors were appearing throughout their lives.

About 12.4 percent of women in the United States will be diagnosed with breast cancer at some point. Image credit:
About 12.4 percent of women in the United States will be diagnosed with breast cancer at some point. Image credit:

Not only did they find that breast cancer rates were four times higher in low fitness rats, but they also discovered that tumors in high fitness rodents appeared later in their lives and were significantly smaller.

Future studies will focus on prevention methods using the right exercise program

The researchers admitted that the results cannot immediately extrapolate to humans, but they want to conduct a similar study in a clinic to find out whether these observations also occur in people.

Nevertheless, further research is needed to be conducted with lab rats to discover strategies to reduce breast cancer risks in low fitness rats and identify what kind and amount of exercise can effectively disconnect low inherent fitness with the development of malign breast tumors. The study authors believe most individuals are able to improve their innate fitness capacity with exercise.

Separate evidence supports the link between exercise and cancer

Researchers found in a 2013 meta-analysis of 31 prospective studies that physical activity helped reduce the average breast cancer risk by 12 percent, according to the National Cancer Institute.

Mammogram, Breast Cancer
Image credit: Getty Images.

There is evidence showing that exercise helps lower the risk of breast cancer in both premenopausal and postmenopausal women but there are stronger proves for the last group.

The institute, part of the U.S. Department of Health and Human Services, lists on its website several biological benefits obtained by doing regular exercise. These positive effects on the body include a decrease of hormone levels (insulin and estrogen) and some growth factors liked to cancer development and progression in cases of breast and colon cancer.

An adequate physical activity also contributes to prevention of obesity and its harmful effects such as insulin resistance. Moreover, exercise helps improve immune system functions.

Adults willing to substantially improve their health should every week engage in an aerobic physical activity for at least 150 minutes if they prefer moderate intensity or 75 minutes if they are ready for vigorous intensity, according to the 2008 Physical Activity Guidelines for Americans recommended by the Department of Health and Human Services.

The department advice adults to perform physical activity in segments of at least 10 minutes spread throughout the week. It recommends the examples of physical activities found on the Physical Activity website of the Centers for Disease Control and Prevention.

The guidelines recommended for children and teenagers include daily exercise for at least one hour, with most of the time dedicated to either moderate- or vigorous-intensity aerobic physical activity. They should commit at least three days a week to vigorous-intensity activity.

Source: Medical Xpress