A significant group by average total daily physical activity interaction (p = .014) suggested all breast cancer survivors, independent of chemotherapy treatment, who engaged in more total physical activity had shorter reaction times for 2-back target trials (radiation only: Est. = −0.13, SE = 0.04, P = .002, R2 = 0.12; chemotherapy: Est. = −0.24, SE = 0.07, p = .002, R2 = 0.27).