It's known as Reynaud's Syndrome. I have it a lot in the winter when it's cold outside and swimming. When my hands warm up they become fire red. You can do a google search of this and find out a lot of information. It's constriction of smaller vessels. I have coronary artery spasms too and wonder if there is some connection with this. Take care, Ally
might be circulation do you get it on your feet too. Do you do any other forms of exercise or just swimming? My mum gets pins and needles but that is because of her diabetes 2.
The cold environment causes a constriction of blood vessels in the extremeties to conserve body heat and funnel resources to the vital organs in the trunk (just in case this is an emergency or long-term situation).