Check your grammar now! : intense or paroxysmal excitement; especially : the rapid pleasurable release of neuromuscular tensions at the height of sexual arousal that is usually accompanied by the ejaculation of semen in the male and by vaginal contractions in the female.
So, even though you may have only burned 250 calories during your HIIT workout, the total calories burned after will be far greater. Those calories, plus the 250 burned during the HIIT workout surpasses the 400 burned during the slow, steady-state workout by a LONG, LONG way.
How to find the sweet spot for HIIT on a Treadmill. When using your treadmill for HIIT workouts, it may take a little experimenting on your part to find the right settings. Both the speed and incline settings can play important roles in designing a great HIIT workout. Try to find a setting that you can sustain for no more than one minute.