Intermittent and Interval Training Decoded – part 2
As we might expect since they were Germans, the original chrono-biologists structured the format of interval training with scientific accuracy. They named one form of interval training recovery (ie: that form which is active and incomplete) as “rich" recovery.
They defined what length of duration it must have to be able to take advantage of the incomplete recovery type, saying it must be one third of the time it would take to have complete recovery. For example: you run your 15 x 400m at your ~5k target pace, and complete cardiovascular recovery (as well as neuro-muscular recovery and lactate clearance) takes between 2:00-3:00 mins, then they defined the “rich recovery” (in this case) as anywhere from 40 secs (one third of 2:00 mins) to 1:00 (one third of 3:00 mins). So, (in this 400s example) complete recovery: 2:00-3:00 mins. Incomplete recovery: 40 secs to 1:00 min.
For skilled, experienced runners, the 1:3 interval recovery works best if, during the short recovery the runner does some easy-to-moderate activity, like gentle jogging.
Old-fashioned determination of the correct length of recovery used to measure the time it took for the HR to get back down to 100-120 bpm after each interval.
Consequently, if you run long intervals like 5 x 1km at your ~5k pace, you need more than 3:00 mins to achieve full recovery. Therefore to maintain the same interval training (incomplete “rich" recovery) workout profile that you did in the example of 15 x 400m, Hadd would suggest you build towards 5-6 x 1k at 5k pace with 200m jog recovery in about 1:30-2:00 mins, and this would be correct according to interval training recovery principles.
Slower runners need longer interval recovery for the same workouts. If a slower runner does the same 5-6 x 1km, he/she will need more time to recover (and here it’s immaterial whether the aim is complete or incomplete recovery); normally relate to the fast runner the slower runner will need more time since the recovery duration depends entirely on the duration of the run.
It’s simple logic: 15 x 400m at ~3k pace” of 80 secs/lap will require more interval recovery than another runner doing 15 x 400m at HIS ~3k pace, when his 3k pace is 63 secs/lap. So, the recovery time is not set by the pace of the interval rep (in which case all those who train at their respective “3k pace” would get the same recovery time), but it is set by the duration of the rep, and 80 secs/400 is longer than 63 secs/400m.
5 x 1km at 5k pace (when 5k pace is 3:45/km) demands more interval recovery time than 5 x 1km (when 5k pace is 3:15/km) and this latter requires more interval recovery than 5 x 1km (when 5k pace is 2:45/km).
But if you want to do an intermittent workout, and your goal is NOT “rich recovery” of the classic interval training type, but instead you simply want to focus on race pace (ie: time trial, check test, all-out run, maximal or supra-maximal run, VO2max ... the name of the workout can have evolved from a number of different concepts), or you wish to run at threshold pace (could be called: LT, LTP, tempo, fartlek, etc), this is no longer interval training; it is fractional or repetition training. In which case, the interval recovery length can be as long as it needs to be, and you may standstill as long as you need to in order to permit/allow you to run your “best pace” in the next repetition. Because, in such a situation, the goal of the workout is no longer “rich recovery” but “fast pace”.
If it’s the case that you want to run 400s or 1kms in the repetition type, then use standstill recovery interval for a long period to allow complete recovery OR go and jog for a period longer than the standstill recovery period.
For example: you run 400s at your ~3k pace with 1:30 standstill recovery OR you jog 200m easy in a time of about 2:00 mins. Another example: you run 1km reps at 5k pace with 3:00-4:00 mins standstill recovery OR you jog 400m recovery in a time longer than 3:00-4:00 mins.
But wait ! If it is the case that you want to run 1km reps, but at threshold pace – somewhere between HM to M pace, or even at 15k/10 mile pace, then all that I have just explained about recovery does NOT apply !
For example: you choose to run 10 x 1km at LT pace. This might be a typical LT workout done in the form of intermittent training. It is slower paced than the usual 1500m, 3k, 5k, or even 10k-pace intervals. Therefore the relatively slow pace must be matched by a short length recovery interval. In this kind of workout you can use the same sort of short and/or active interval that you might use when running typical 200m or 400m reps and the goal is incomplete “rich recovery” interval.
So for 10 x 1km at LT pace (HM to M, or 15k/10 mile pace) you can use 1:00-2:00 standstill interval recovery.
Having said that, please note that I have my own personal methodological argument to prefer 2:00-5:00 mins easy jog recovery in this situation rather than (what I would call) “crazy” 1:00 min recovery.