13 Interval Training Workouts That Change Your body-SliderPhoto


9. Senior HIIT
Mark J. Smith, a former professional rugby player and interval training expert, believes the elderly should not limit themselves to light or even moderate exercise. Smith said in a 2008 study that, more than any other age group, “the elderly need vigorous exercise.” By vigorous, he means using a method of conditioning with sprint-interval or high-intensity intervals, commonly referred to as SIT and HIIT.