Research found that doing 10-20-30 intervals can improve 5K time and VO2 max, even if you don’t go at maximum effort. Experts suggest adding this workout to your schedule one to two times per week.

There’s a lot of talk in the exercise world about high intensity interval training (HIIT) lately, which is exactly what it sounds like — alternating episodes of exercise with periods of less intensive ...

There comes a time in every runner’s life when it’s time to kick things up a notch. That means one thing and one thing only: interval training. There’s a reason loads of runners don’t like intervals.