@Maree72 In Dec. '17, I had a lumpectomy followed by radiotherapy in Feb/March '18 & like you, I am a keen exerciser. I used Mepitel film during my radio treatment so didnt have any burning or skin irritation at all so I was back exercising soon after treatment. Everyone is different so listen to your body & of course, be guided by your BC Nurse & surgeon. I think its great that you want to get back into exercise like I did!! I dont do any water sports but like running, walking & strength exercises.
Following my rad treatment which ended in March '18, I was back running 10km by the end of the year, which was my goal. To this day, I still do the BC Pilates routine from the CD I received in hospital & do this 4 times a week following my run. Exercising helped me greatly, physically, emotionally & mentally, as it made me feel "normal" following my surgery & treatment. Pace yourself & listen to your body & if your medical team are happy for you to exercise, then 'you go girl"!! I run 40kms a week now & have done two half marathons. I was very lucky with my treatment & surgery outcome & i hope you are too so you can get back & enjoy the water sports you love. Love & strength xx <3