Table 3.

Studies about the influence of physical activity (PA) on recurrence and survival

Study	Design	Recommendations/statement from the authors
[64]	• meta-analysis of published studies • included 6 studies with 12,108 breast cancer patients	• ‘post-diagnosis PA reduced - breast cancer deaths by 34% - all causes mortality by 41% - disease recurrence by 24%’ • ‘… evidence for an inverse relationship between PA and mortality …’
[5]	• review of evidence	• ‘certain patient subtypes are more responsive to physical activity than others’ - ‘observe/note possible responsiveness to exercise’ • ‘strongest evidence for an association between post-diagnosis physical activity and cancer-specific mortality is found for breast and colon cancers for which the average mortality risk decrease is 25 and 32%, respectively’
[65]	• meta-analysis of cohort studies • included 16 cohort studies with 42,602 breast cancer patients	• ‘… both pre-diagnosis and post-diagnosis PA were associated with reduced breast cancer-specific mortality and all-cause mortality’
[9]	• review	• ‘… 24–67% reduction in the risk of total deaths and 50–53% reduction in the risk of breast cancer deaths in women who are physically active after breast cancer diagnosis compared with sedentary women’
[46]	• prospective observational study of 933 women with breast cancer	• ≥9 metabolic equivalents (METs)/week (e.g., 2–3 h/week of brisk walking) - before and especially after diagnosis and treatment • ‘women who increased physical activity after diagnosis had a 45% lower risk of death’ • ‘moderate-intensity physical activity after a diagnosis of breast cancer may improve prognosis’
[45]	• randomized controlled trial with 2,361 post-treatment breast cancer survivors (stage I–III)	• ‘… most active at baseline had a 53% lower mortality risk compared to the least active women. Adherence to activity guidelines was associated with a 35% lower mortality risk’ • ‘42% reduction in risk mortality among those women who were adhering to physical activity guidelines at both baseline and 1-year relative to those who did not meet the guideline at either time point’ • ‘we did not find that 1-year change in physical activity was associated with breast cancer mortality’
[66]	• systematic review and meta-analysis • used PRISMA guidelines • included 16 studies with breast cancer survivors and 7 studies with colorectal cancer survivors (49,095 cancer survivors)	• ‘… engaging in the approximate equivalent of 150 min of at least moderate physical activity per week after cancer diagnosis was associated with a 24% reduced risk of total mortality among breast cancer survivors’ • ‘comparable amount of physical activity performed pre-diagnosis was related to a 13% reduced total mortality risk among breast cancer survivors’ • ‘… benefit of physical activity was evident for both lean and overweight women, for pre- and post-menopausal women, and for ER-positive and -negative tumors’
[67]	• data collection from breast cancer survivor cohorts in a after breast cancer pooling project with 9,513 patients	• ‘very low physical activity was associated with a 22% increased risk of breast cancer mortality’ - very low physical activity: ‘… defined as physical activity < 1.5 MET-h/week …’ and ‘… equivalent to <30 min of moderate paced walking per week’
[68]	• prospective cohort study with 3,393 non-metastatic breast cancer patients	• ‘risk for recurrence was about 50% reduced in patients with estrogen/progesterone receptor-negative (ER−/PR−) tumors who had been physically active pre-diagnosis, e.g., cycled or exercised at least 1 h/day, compared to physically inactive women’ • ‘among patients with ER−/PR− breast tumors, higher levels of exercise may even reduce their risk of recurrence’ • ‘… there was no mortality reduction with increasing PA levels.”
[69]	• international open-label randomized controlled trial with 521 breast cancer patients	• ‘overall survival was better for patients who were active before and after the diagnosis. In contrast with previous studies, breast cancer survival and the risk of recurrence were not significantly associated with physical activity’
[70]	• systematic review and meta-analysis of epidemiological studies • 22 prospective cohort studies with 123,574 participants	• ‘… significant associations between lifetime and recent pre-diagnosis recreational physical activity and risk of all-cause death …’ • ‘… recent pre-diagnosis recreational physical activity was also found to be associated with the risk of breast cancer-related death’ • ‘post-diagnosis physical activity was found to significantly reduce the risk of both all-cause death and breast cancer-related death’
[71]	• prospective observational study based on responses • from 2,987 breast cancer patients	• ‘physical activity after a breast cancer diagnosis may reduce the risk of death from this disease. The greatest benefit occurred in women who performed the equivalent of walking 3–5 h per week at an average pace, with little evidence of a correlation between increased benefit and greater energy expenditure’