Interval training = Methodic training with the change between work and rest periods (=Interval).
Interval training is well known in human professional sport, but has never really been transferred into the horse world.
By having the horse walk/trot in a 8m square, the outside muscles are able to stretch, the inside muscles shorten. This creates bend through the whole body (from head to tail). No muscle can work for 7 minutes and no horses can concentrate for more than 7 minutes in a row. This has been known for centuries by horse trainers in the cavalry who worked with thousands of horses to train them for war and for non-experienced riders.
Today some horses get asked to work and concentrate for 45 minutes or even more, which is way too much for both their minds and bodies!
That is why Equikinetic and Dualactivation use rest periods as a release for muscles and brain.
The length of the rest period does not provide enough time for a complete recovery. That is why interval training has such a high training impulse.
Furthermore, the horse is motivated to work because it knows that after 1 minute it has a break. If someone asked you to run for 13 minutes in a row or 8x for 1 min with a 45 sec. break in between, what would you rather do?
We use a cellphone app called Impetus as an interval manager. The timer gives the training more structure then normal lunging. It makes sure that both sides get worked evenly.