The Who, What, Where, When and Sometimes, Why.

Research table: Exercise (physical activity) and breast cancer risk

This summary table contains detailed information about research studies. Summary tables are a useful way to look at the science behind many breast cancer guidelines and recommendations. However, to get the most out of the tables, it’s important to understand some key concepts. Learn how to read a research table.

Introduction: Women who get regular exercise (physical activity) have a lower risk of breast cancer than women who don’t exercise regularly or are inactive. 

Overall, studies show regular exercise is linked to a 10%-20% decreased risk of breast cancer (see table below). This benefit is seen most clearly in postmenopausal women, but study findings also show a benefit in premenopausal women.

Learn more about exercise and breast cancer risk

Learn about exercise and breast cancer survival.

Learn about the strengths and weaknesses of different types of studies.

See how this risk factor compares with other risk factors for breast cancer

Study selection criteria: Prospective cohort studies with at least 800 breast cancer cases, pooled analyses and meta-analyses.

Table notes: Relative risk above 1 indicates increased risk. Relative risk below 1 indicates decreased risk. 

MET (metabolic equivalent) hours are often used as a measure of physical activity. One MET hour equals the energy used to sit quietly for one hour. 

Different activities have different MET scores. Moderate activities, like mowing the lawn or slow dancing, range from 3-6 MET hours. Vigorous activities, like playing tennis or jogging, score higher than 6 MET hours. For example, walking is 3 MET hours and swimming is 7 MET hours.

Study

Study Population
(number of participants)

Follow-up
(years)

Levels of Activity Compared

Relative Risk of Breast Cancer in Physically Active Women Compared to Inactive Women, RR (95% CI)

Before menopause

After menopause

Before and after menopause combined

Prospective cohort studies

EPIC [1]

257,805
(8,034 cases)

12

More than 42
vs.
14 or fewer MET hr/wk recreational activity

0.88
(0.72-1.07)

0.97
(0.91-1.05)

0.96
(0.90-1.03)

NIH-AARP Diet and Health Study [2]

106,126
(7,088 cases)

13

At least 4 hr/wk
vs.
inactive

 

0.91
(0.84-0.98)

 

Nurses’ Health Study [3]

95,396
(4,782 cases)

20

27 or more
vs.
less than 3 MET hr/wk

 

0.88
(0.79-0.98)

 

Cancer Prevention Study II-Nutrition Cohort [4]

73,615
(4,760 cases)

13

More than 42 vs.
7 or fewer MET hr/wk

 

0.75
(0.63-0.89)

 

 

  

7 or more
vs.
3 or fewer hr/wk walking

 

0.86
(0.75-0.98)

 

French E3N cohort [5-6]

90,509
(3,424 cases)

11

22-34 MET hr/wk recreational activity
vs.
inactive

  

0.88
(0.79-0.98)

 

 

 

34 or more MET hr/wk recreational activity
vs.
inactive

  

0.81
(0.72-0.92)

UK Biobank [7]

184,608
(3,189 cases)

6

High
vs.
low level of activity

0.77
(0.62-0.96)

0.83
(0.74-0.93)

California Teachers Study [8]

110,599
(2,649 cases)

7

58 or more MET hr/wk physical activity
vs.
low level of physical activity

  

1.03
(0.88-1.19)†

Women’s Health Initiative [9]

155,723
(2,610 cases)

8

17 or more hr/wk
vs.
no activity

 

0.85
(0.74-0.98)

 

Iowa Women’s Health Study [10]

36,363
(2,548 cases)

15

High
vs.
low level of activity

 

0.91
(0.82-1.01)

 

National Breast Cancer Screening Study-Canada [11]

40,318
(2,545 cases)

16

At least 1 hr/day vigorous physical activity
vs.
inactive

0.87
(0.68-1.09)

1.00
(0.78-1.29)

0.93
(0.78-1.10)

Norwegian-Swedish Women’s Lifestyle and Health Cohort Study [12]

99,504
(1,166 cases)

9

Vigorous activity
vs.
no activity

1.24
(0.85-1.82)

  

Breast Cancer Detection Demonstration Project Follow-up Study [13]

32,269
(1,506 cases)

8

High
vs.
low level of activity

 

0.87
(0.74-1.02)

 

Netherlands Cohort Study [14]

62,537
(1,208 cases)

7

More than 90 minutes/day of activity
vs.
less than 30 minutes/day

 

0.76
(0.58-0.99)

 

Rainey et al. [15]

57,654
(957 cases)

4-6

1½-2½
vs.
less than 1½ hr/day recreational activity

  

1.07
(0.90-1.27)

 

 

 

2½ or more
vs.
less than 1½ hr/day recreational activity

  

1.11
(0.94-1.31)

U.S. Radiologic Technologies cohort [16]

45,631
(864 cases)

9

At least 97
vs.
less than 10 MET hr/wk

  

0.91
(0.74-1.13)

 

 

 

Walking/hiking at least 10 hr/wk
vs.
never walking/hiking

  

0.57
(0.34-0.95)

Nurses’ Health Study II [17-18]

110,468
(849 cases)

10

27 or more
vs.
less than 3 MET hr/wk

1.04
(0.82-1.33)

  

Pooled and meta-analyses

Nielson et al. [19]

58 studies

 

High
vs.
low level of moderate to vigorous activity

 

0.79
(0.74-0.84)‡

 

 

43 studies

 

High
vs.
low level of moderate to vigorous activity

0.80
(0.74-0.87)‡

 

 

Pizot et al. [20]

38 studies
(116,304 cases)

 

High
vs.
low level of activity

0.87
(0.78-0.96)

0.88
(0.85-0.91)

0.88
(0.85-0.90)

Kyu et al. [21]

35 studies

 

10-67
vs.
less than 10 MET hr/wk

 

 

0.97
(0.94-1.00)

Hardefeldt et al. [22]

35 studies

 

High
vs.
low level of low to moderate activity

  

0.73
(0.65-0.81)

 

 

 

High
vs.
low level of vigorous activity

  

0.79
(0.72-0.86)

World Cancer Research Fund International – Continuous Update Project [23]

21 studies

 

High
vs.
low level of recreational activity

 

0.88
(0.82-0.94)

 

 

12 studies

 

High
vs.
low level of recreational activity

0.89
(0.75-1.04)

 

 

Timmins et al. [24]

19 studies
(10,231 cases)

 

High
vs.
low level of recreational activity

0.90
(0.85-0.95)

 

Physical Activity Collaboration of the National Cancer Institute’s Cohort Consortium [25]

10 studies

 

High
vs.
low level of activity

  

0.93
(0.90-0.96)

Matthews et al. [26]

8 studies
(17,983 cases)

 

1-7 MET hr/wk
vs.
low level of activity

  

0.94
(0.91-0.97)

   

8 to less than 15 MET hr/wk
vs.
low level of activity

  

0.90
(0.86-0.94)

   

15 to less than 30 MET hr/wk
vs.
low level of activity

  

0.88
(0.84-0.91)

   

30 or more MET hr/wk
vs.
low level of activity

  

0.86
(0.82-0.90)

African American Breast Cancer Epidemiology and Risk (AMBER) Consortium [27]

4 studies
(3,856 cases)

 

High
vs.
low level of vigorous activity

 

 

0.88
(0.81-0.96)

† Findings also showed a decreased risk of estrogen receptor-negative breast cancers among women with the highest levels of physical activity (more than 5 hours per week vs. inactive, relative risk was 0.53 (0.33-0.85)). There was no link between physical activity and the risk of estrogen receptor-positive breast cancers.

‡ Findings for cohort studies only were similar. The relative risk for 13 cohort studies of premenopausal breast cancer risk was 0.83 (0.72-0.96). The relative risk for 26 cohort studies of postmenopausal breast cancer risk was 0.90 (0.85-0.95). 

References

  1. Steindorf K, Ritte R, Eomois PP, et al. Physical activity and risk of breast cancer overall and by hormone receptor status: The European prospective investigation into cancer and nutrition. Int J Cancer. 132(7):1667-78, 2013.
  2. Cifu G, Arem H. Adherence to lifestyle-related cancer prevention guidelines and breast cancer incidence and mortality. Ann Epidemiol. 28(11):767-773, 2018.
  3. Eliassen AH, Hankinson SE, Rosner B, Holmes MD, Willett WC. Physical activity and risk of breast cancer among postmenopausal women. Arch Intern Med. 170(19):1758-64, 2010.
  4. Hildebrand JS, Gapstur SM, Campbell PT, Gaudet MM, Patel AV. Recreational physical activity and leisure-time sitting in relation to postmenopausal breast cancer risk. Cancer Epidemiol Biomarkers Prev. 22(10):1906-12, 2013.
  5. Tehard B, Friedenreich CM, Oppert JM, Clavel-Chapelon. Effect of physical activity on women at increased risk of breast cancer: results from the E3N cohort study. Cancer Epidemiol Biomarkers Prev. 15(1):57-64, 2006.
  6. Fournier A, Dos Santos G, Guillas G, et al. Recent recreational physical activity and breast cancer risk in postmenopausal women in the E3N cohort. Cancer Epidemiol Biomarkers Prev. 23(9):1893-902, 2014.
  7. Guo W, Fensom GK, Reeves GK, Key TJ. Physical activity and breast cancer risk: results from the UK Biobank prospective cohort. Br J Cancer. 122(5):726-732, 2020.
  8. Dallal CM, Sullivan-Halley J, Ross RK, et al. Long-term recreational physical activity and risk of invasive and in situ breast cancer: the California teachers study. Arch Intern Med. 167(4):408-15, 2007.
  9. Phipps AI, Chlebowski RT, Prentice R, et al. Body size, physical activity, and risk of triple-negative and estrogen receptor-positive breast cancer. Cancer Epidemiol Biomarkers Prev. 20(3):454-63, 2011.
  10. Bardia A, Hartmann LC, Vachon CM, et al. Recreational physical activity and risk of postmenopausal breast cancer based on hormone receptor status. Arch Intern Med. 166(22):2478-83, 2006
  11. Silvera SAN, Jain M, Howe GR, et al. Energy balance and breast cancer risk: a prospective cohort study. Breast Cancer Res Treat. 97(1):97-106, 2006.
  12. Margolis KL, Mucci L, Braaten T, et al. Physical activity in different periods of life and the risk of breast cancer: the Norwegian-Swedish Women’s Lifestyle and Health cohort study. Cancer Epidemiol Biomarkers Prev. 14(1):27-32, 2005.
  13. Leitzmann MF, Moore SC, Peters TM, et al. Prospective study of physical activity and risk of postmenopausal breast cancer. Breast Cancer Res. 10(5):R92, 2008.
  14. Dirx MJ, Voorrips LE, Goldbohm RA, et al. Baseline recreational physical activity, history of sports participation, and postmenopausal breast carcinoma risk in the Netherlands Cohort Study. Cancer. 92(6):1638-1649, 2001.
  15. Rainey L, Eriksson M, Trinh T, et al. The impact of alcohol consumption and physical activity on breast cancer: The role of breast cancer risk. Int J Cancer. 147(4):931-939, 2020.
  16. Howard RA, Leitzmann MF, Linet MS, Freedman DM. Physical activity and breast cancer risk among pre- and postmenopausal women in the U.S. Radiologic Technologists cohort. Cancer Causes Control. 20(3):323-33, 2009.
  17. Colditz GA, Feskanich D, Chen WY, Hunter DJ, Willett WC. Physical activity and risk of breast cancer in premenopausal women. Br J Cancer. 89(5):847-51, 2003.
  18. Maruti SS, Willett WC, Feskanich D, Rosner B, Colditz GA. A prospective study of age-specific physical activity and premenopausal breast cancer. J Natl Cancer Inst. 100(10):728-37, 2008.
  19. Neilson HK, Farris MS, Stone CR, Vaska MM, Brenner DR, Friedenreich CM. Moderate-vigorous recreational physical activity and breast cancer risk, stratified by menopause status: a systematic review and meta-analysis. Menopause. 24(3):322-344, 2017.
  20. Pizot C, Boniol M, Mullie P, et al. Physical activity, hormone replacement therapy and breast cancer risk: A meta-analysis of prospective studies. Eur J Cancer. 52:138-54, 2016.
  21. Kyu HH, Bachman VF, Alexander LT, et al. Physical activity and risk of breast cancer, colon cancer, diabetes, ischemic heart disease, and ischemic stroke events: systematic review and dose-response meta-analysis for the Global Burden of Disease Study 2013. BMJ. 354:i3857, 2016.
  22. Hardefeldt PJ, Penninkilampi R, Edirimanne S, Eslick GD. Physical activity and weight loss reduce the risk of breast cancer: a meta-analysis of 139 prospective and retrospective studies. Clin Breast Cancer. 18(4):e601-e612, 2018.
  23. Chan DSM, Abar L, Cariolou M, et al. World Cancer Research Fund International: Continuous Update Project-systematic literature review and meta-analysis of observational cohort studies on physical activity, sedentary behavior, adiposity, and weight change and breast cancer risk. Cancer Causes Control. 30(11):1183-1200, 2019.
  24. Timmins IR, Jones ME, O’Brien KM, et al. International pooled analysis of leisure-time physical activity and premenopausal breast cancer in women from 19 cohorts. J Clin Oncol. 42(8):927-939, 2024.
  25. Moore SC, Lee I-M, Weiderpass E, et al. Association of leisure-time physical activity with risk of 26 types of cancer in 1.44 million adults. JAMA Intern Med. 176(6):816-25, 2016.
  26. Matthews CE, Moore SC, Arem H, et al. Amount and intensity of leisure-time physical activity and lower cancer risk. J Clin Oncol. 38(7):686-697, 2020.
  27. Gong Z, Hong CC, Bandera EV, et al. Vigorous physical activity and risk of breast cancer in the African American breast cancer epidemiology and risk consortium. Breast Cancer Res Treat. 159(2):347-56, 2016.

Updated 06/06/24

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