Also from the previous thread:
@Silkiebunny
Thanks for your reply and link! I clicked on the study they were referencing about the 3-5 hours and found the following info which I'm pasting here in case it's helpful to other people too:
Three MET-hours is equivalent to walking at average pace of 2 to 2.9 mph for 1 hour.
The benefit of physical activity was particularly apparent among women with hormone-responsive tumors. The RR of breast cancer death for women with hormone-responsive tumors who engaged in 9 or more MET-hours per week of activity compared with women with hormone-responsive tumors who engaged in less than 9 MET-hours per week was 0.50 (95% CI, 0.34-0.74). Compared with women who engaged in less than 3 MET-hours per week of activity, the absolute unadjusted mortality risk reduction was 6% at 10 years for women who engaged in 9 or more MET-hours per week.
Conclusions: 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 to 5 hours per week at an average pace, with little evidence of a correlation between increased benefit and greater energy expenditure. Women with breast cancer who follow US physical activity recommendations may improve their survival.
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https://pubmed.ncbi.nlm.nih.gov/15914748/
I'm not hormone-responsive (well, at least not ER or PR, who knows about AR etc) but I think it's very helpful to have this guideline. Thank you @Silkiebunny In any case, I can't picture them having had enough or possibly any Her2+++ Er-0 Pr-0 patients back then who survived, so they might also have had similar benefit. The study was done with women diagnosed 1984-98, so I think that's pre the Her2 MABs etc.
It's very encouraging too that it doesn't have to be high impact sport, normal walking is good!!