This is on of my favorite icing on the cake workouts. This workout can be used in the final 8-10 weeks before a 5k or 10k or in the final 4-6 weeks before a half marathon or marathon. It is intended to work on economy and put a little bit of snap in your legs. As alluded to in the name, it’s an aerobically based workout disguised as a more traditional hard interval session. Many people refer to these as cruise intervals. The beauty is you get a lot of the same benefits as a tempo run, but at a faster pace.
The key is in the controlled pacing of the repeats. The number of repeats should vary, depending on your training level and experience, from 2-4 sets of (3-4x400m). The recovery should be 45-50 seconds between repeats and 2:00-2:30 between sets. Start the first set at or 5-10sec/mile quicker than 10k pace and finish the final set at 5k pace or even a few ticks quicker. You should finish feeling in control and comfortable. This is a great confidence booster in the final few weeks before a race as you will be surprised how good you will feel running relatively fast.