“During most all of human evolution, it was adaptive to conserve energy by being lazy as circumstances permitted. Energy was a vitally needed resourse and could not be wasted. Today this take-it-easy adaptation may lead us to watch tennis on television when we would be better off playing it. This can only aggravate the effects of excess nutrition. The average office worker would be much more healthy if he or she spent the day digging clams or harvesting fruit in scattered tall trees.”