I have very sun sensitive skin also. I also like to snorkel, cycle and kayak. I went to a dive shop and was introduced to a snorkeling suit made for people like us. It was a one piece suit made of a very light weight material that covered everything but my neck and head. It absorbs any sweat and dries really fast. Since I have started using it I am sunburn free for quite a while now. I almost gave up many outdoor sports until I found this. You can wear clothes over it for that svelte cycling look. Hope this helps. Also have started to use the skull caps that footballplayers wear under their helmets.