I think it varies from person to person dependent on hm radiotherapy and how your body reacts eg skin damage and fatigue. I am very fair but surprisingly skin impact was minimal but do note I creamed up 3 times daily with Dermaveen and still am 2.5 months later. We went to Cairns 4 weeks after and was careful with uv eg rashie in pool but no lengthy uv exposure eg no 8 hour outer reef snorkelling for me.Had noticeable fatigue the week after radiotherapy finished - did an exercise class the morning after and slept the afternoon - but otherwise ok .I also only had 16 sessions of radiotherapy.I think re tiredness the key might to be taking things at a relaxed pace after treatment but talk to your radiation onc and nurse plus give yourself some time to see how your body goes during treatment.Also radiotherapy is intense as it's daily going back and forth ( including trying to find a park) to get zapped you might like a bit of time to slow down from it all