After the virile old man celebrated his 100th birthday, a reporter asked him the secret of his energy.
Old man: “Well, after getting married, my wife and I agreed that whoever lost the argument after an altercation should walk 5 km as punishment. So, for the past 75 years, I have been walking 5 km almost every day.”
Reporter: “Then how come your wife too, is energetic as you are?”
Old man: “Oh, she used to follow me at a distance to ascertain whether I completed the 5 km walk and moreover to make sure I meet no other women!”