what are the exercises for increasing sex stamina: 1. Tongue Ever had your tongue or jaw cramp up during oral sex? You know it wasn’t fun for you and it definitely wasn’t for her. Strengthen your jaw and tongue muscles by doing tongue push-ups. Push the underside of the tip of your tongue into the front of your hard palate (the front of the roof of your mouth, right behind your front teeth). Do this enough times with enough strength and it will become easier over time (giving you more sexual stamina for oral sex).