I read in a New York Times article the other day that strenuous exercise can temporarily weaken the immune system. Whereas, moderate exercise, generally, seems to strengthen the immune system.
Surfing in freezer water is probably considered strenuous exercise. I stay busy, by catching lots of waves, because I don't like going to the gym.
After a surf, I boost my immune system with Emergen-C, an electrolyte, vitamin C and B powdery mixture. (Mix packet with glass of water) Just in case, the article in the New York Times is right.
