Author: National Cancer Institute (NCI)
The sports referred to here include dance, physical exercise, housework and leisure activities, and specific sports include walking, tennis, cycling and swimming.
There is a lot of evidence that exercise is associated with a reduced risk of developing several cancers.
1. Colon cancer
The relationship between colon cancer and movement is the most studied of cancer.
A 2009 epidemiological study of 52 studies on the relationship between exercise and colon cancer found that those who exercised the most had a 24% lower risk of developing colon cancer compared to those who exercised the least.
A pooled analysis of data from 12 prospective US and European cohort studies on recreational exercise found that those who exercised the most had a 16% lower risk compared to those who exercised the least.
The incidence of distal and proximal colon cancer decreased in people who exercised more compared to those who exercised less.
Exercise is also associated with a reduced risk of colon adenomas (polyps), which may progress to colon cancer.
However, it is unclear whether exercise is associated with a reduced risk of recurrence after polyp removal.
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Second, breast cancer
Many studies have shown that women who exercise more have a lower risk of developing breast cancer than women who exercise less.
A 2013 meta-analysis of 31 prospective studies found that exercise reduced breast cancer risk by an average of 12%.
In both premenopausal and postmenopausal women, exercise was associated with a reduced risk of breast cancer; however, in postmenopausal women, the evidence of correlation was stronger.
Women with increased postmenopausal exercise also had a lower risk of breast cancer than women who did not exercise.
3. Endometrial cancer
Many studies have investigated the relationship between exercise and endometrial cancer risk.
In a meta-analysis of 33 studies, people who exercised more had an average 20% lower risk of endometrial cancer than those who exercised less.
There is evidence that the relationship between exercise and endometrial cancer risk may reflect the role of exercise in obesity, which is a known risk factor for endometrial cancer.
Other cancers
Evidence of a relationship between other cancers and exercise is limited.
In a study of more than 1 million people, recreational exercise was associated with a reduced risk of esophageal adenocarcinoma, liver cancer, gastric cardia cancer (a type of gastric cancer), kidney cancer, myeloid leukemia, myeloma, and head and neck cancer, rectum, and bladder cancer. These results were confirmed by large cohort studies or meta-analyses.
However, it should be noted that almost all of the evidence on the relationship between exercise and cancer risk comes from observational studies that can find a link between exercise and cancer, but do not determine whether there is a causal relationship between the two.
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5. What are the potential anti-cancer effects of exercise?
Exercise has a variety of biological effects on the body, some of which may help prevent cancer, including:
Lowering levels of hormones, such as insulin and estrogen, as well as specific growth factors associated with the development and development of cancer;
Prevention of obesity, alleviating the harmful effects of obesity, especially the prevention of insulin resistance (i.e. the inability of human cells to respond to insulin);
Reduces inflammation;
Improves the function of the immune system;
altering bile acid metabolism, reducing the exposure of the gastrointestinal tract to these suspected carcinogens;
Reduces the time it takes for food to pass through the digestive tract and reduces the exposure of the gastrointestinal tract to potential carcinogens.
6. What are the harms of sitting for a long time to the body?
Sedentary hours, such as watching TV for long periods of time, sitting and lying down, are risk factors for many chronic diseases, including cancer, cardiovascular disease, type 2 diabetes and early death.
In some studies, even exercise has not reduced the increased risk of disease due to prolonged sitting.
However, in a large meta-analysis, an increase in cancer mortality was observed only in sedentary people with less exercise.
7. How should I exercise?
1. Adults
The 2008 U.S. Exercise Guidelines recommend that, in order to reap significant health benefits, adults should do at least:
150 minutes (2.5 hours) of moderate-intensity aerobic activity,
75 minutes (1.25 hours) of high-intensity aerobic activity,
Or an equal combination of moderate and high intensity activities.
Aerobic activity should be at least 10 minutes each time, preferably spread out.
Moderate-intensity activities include:
Go fast;
Swimming;
Cycling (< 16 km / h);
Tennis (doubles);
Ballroom dancing.
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High-intensity activities include:
Race walking, jogging or running;
Tennis (singles);
Cycling (≥ 16 km / h);
Skipping rope;
Hike up a mountain or carry a weight.
2. Children and adolescents
Guidelines recommend that children and adolescents exercise for at least 1 hour a day, with moderate or high-intensity aerobic exercise, as well as appropriate muscle and bone strengthening training. At least 3 days a week.
*The content of this article is a popularization of health knowledge and cannot be used as a specific diagnosis and treatment recommendation, nor is it a substitute for face-to-face consultation by a practicing physician, for reference only.
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