Ancient Greek philosopher Aristotle considered laughter as “a bodily exercise precious to health.” But ­­despite some claim s to the contrary, laughing probably has 36 influence on physical fitness. Laughter does 37 short-term changes in the function of the heart and its blood vessels, 38 heart rate and oxygen consumption. But because hard laughter is difficult to 39 , a good laugh is unlikely to have measurable 40 the way, say, walking or jogging does.