Hi Red,
Yip keeping up exercise is good but don't try to over do it from your initial fitness to quick. It took me about a year after chemo before I could start jogging, which I hadn't done for a long time. I did however keep walking, hill and flat and gardening, swimming etc.
During chemo I just did walking and keep active however come session 4 etc fatguie set in and I had to listen to my body and sleep or nap whenever I needed. Rest was very important.
Steven