do a circuit workout, chose 3 or four exercises, squats, situps pushups, for example, start at 10 and do ten each and work your way down to 1 each without taking any breaks, increase amount of exercise and number of reps as necessary. Do it as fast as you can while keeping good form, if your form is off restart
laughing and sex
Distance Running, it's not sex I know that for sure.
Walking and running of course.