The Perfect Running Interval

Run interval workouts are key for boosting fitness, but you've got to do them the right way to really get the most from them. Here's how.

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Interval running workouts are a sure-fire way to boost your speed and endurance, but you’ve got to know the right way to build these sessions into your training. While endurance buffs often revel in long, slow runs, any good training regimen will always include some high-intensity sessions. This often comes in the form of interval training, which can create significant jumps in fitness. “Ultimately, as endurance athletes, we want to be able to sustain as fast a speed as possible over the duration of our events,” said Krista A. Schultz, an exercise physiologist and triathlon coach for Endurance Works in Boulder, Colorado. “Proper training including workouts aimed at increasing speed will improve one’s lactate threshold (LT), the point at which lactate is produced at such a rapid rate it cannot be cleared. The benefit of interval training is that it helps us increase our LT.”

New research offers insight into the ideal length of running intervals, as well as how to best recover. Researchers at the Mayo Clinic pulled together 37 separate studies on interval run training and VO2max to get a clearer picture of what scientists collectively know about interval training. They identified running intervals from three to five minutes as being the most effective.

Another recent study out of Great Britain examined the recovery piece. While some coaches favor complete rest between running intervals, this research revealed that active recovery was more effective in clearing metabolites from the muscles. This, in turn, allows athletes to recover faster between high-intensity bouts when they keep moving, which also likely leads to better performance during those subsequent intervals. “Running easy or jogging between intervals will help clear lactic acid quicker because it is being reused as fuel at a faster rate when you’re moving around,” Schultz said.

The next time you’re headed to the track, trail or treadmill for some high-intensity training intervals, consider the following workouts. Start with Workout 1 before graduating to #2, then #3. Keep in mind that run intervals should not be performed all-out. This means that it should feel difficult, but you shouldn’t be sprinting. The point of these workouts is to be able to do multiple intervals, not crash and burn after the first set.

RELATED: Interval Workouts To Try On The Track

3 Top Interval Run Workouts

Workout 1

– Warm up 10 min
– 5×3 min at 5K pace
– Jog easy for 3 min between each
– Cool down 10 min

Workout 2

– Warm up 10 min
– 4×4 min at 5K pace
– Jog easy for 2 min between each
– Cool down 10 min

Workout 3

– Warm up 10 min
– 4×5 min at 5K pace
– Jog easy 2:30 between each
– Cool down 10 min

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