The theory is that exercise alleviates stress and benefits women psychologically which improves their memory.
"A surprising finding is memory problems appear to be related to the high stress load cancer survivors experience, and may not be specific to chemotherapy or radiation treatments."
That's surprising? To me this is even more important than figuring out that exercise improves memory. Seriously, I could have told you that a cancer diagnosis causes incredible stress. It just amazes me how many people do not get that part. Obviously they haven't been diagnosed with cancer.