And finally, tired from the exertion of surfing Hilton takes us back to his local neighbourhood of Bernal Heights for a relaxing massage at Integral Body, concluding his idea of a perfect morning in San Francisco.

BBC: The Real San Francisco

From couch potatoes to Olympic athletes, everyone has a physical capacity for exertion, beyond which the body becomes stressed and begins to feel bad.

WSJ: Hard-Wired to Hate Exercise?