Interval Training
Interval training is the product of science. It’s was one of the first results of laboratory testing applied to the training methods of runners.
In the 1930s Dr. Woldemar Greschler refined “stop-and-go” training to an exact science based on a runner’s heart rate.
Here’s Greschler defining the exact guidelines to interval training:
“The running effort in interval training should send the heart rate to around 180 beats per minute. For this point, the heart is allowed no more than 90 seconds to return to 120-125bmp. If it takes longer, the running effort demanded has either been too violent or too long.”
Interval training has endured for almost 100 years as a go-to method for improving running performance because it works. The beauty of intervals is its endless adaptability. It can be used for endurance training, pace work, speed work — or a combination of all three.
There are 5 variables the interval trainer can play with, identified by the acronym D.I.R.T.Y.:
Distance of the fast run
Interval of the rest or recovery between fast runs
Repetitions of fast runs in a workout
Time of the fast runs
Your activity (walking, standing, jogging, steady running) between fast runs.
“Interval” refers to the recovery period between the runs, rather than the run itself.
Why?
This traces back to the developers theory that the heart’s action during the recovery phase is the decisive factor of a workout’s effectiveness. To repeat, what matters most in interval training is not the speed of the faster repetition runs, but how quick (or long) it takes the heart rate to recover to 120 bpm after each fast run.
The rest period, not the pace of the work period, is the deciding limiting factor to improvement. Therefore, the primary aim of correct application of interval training is to advance the recovery intervals between fast runs by making the recovery times shorter or recovery activity incrementally more moderate.