You are all wrong !
The workout on the graph it´s not 16X(400m+200m)with 90s-120secs rest and not 8X(400m+200m) as well.
WHAT THE GRAPH SHOWS IS 1X200m+(8X400m+200m) or put in another way but that is the same the graph shows is
8X200m+400m)+200m.
THE WORKOUT STARTS WITH 200m AND NOT 400m. STARTS with 200m AND FINISHES WITH ANOTHER 200m. ABSOLUTELY ! The first set is 200m and the last set is another 200m again.
About the recovery length, what the graph shows is that the first recovery periods are about 90-96secs duration AND the recovery duration goes longer and longer, and the last 2 recovery periods are about 2:30min duration.
This changes quite completely the initial technical interpretation, the one done by the author of the article, that bases his conclusion in wrong and inaccurate data.
On a methodological analysis, and just by the HR graph analysis of this workout, I can say it wasn´t been as hard as some might think, because several reasons.
Despite the pace could be fast eventually, the runner that did it could resist to run it with low HR, and the long recovery length duration periods – that are longer recovery for every next set – results in a lower HR decrease, and on every new set, his heart and cardio-vascular systems are quite recovered. We can say this is not a straight interval training, the kind of interval training that the recovery is so short that the runner haven´t opportunity and he can´t get his HR down, the way each new set his heart goes higher and higher in crescendum, and the heart after each recovery period doesn´t go down from 140-145 HR, it´s what happens on a experienced runner like would be Bekele.
Another aspect is the number of posts with people that are impressionate by what Bekele supposedly did. Fantastic, very good, astonish workout, etc.
I taught that one day we will have a Olympic competition for the world´s best workout, or we try to put this kind of workouts in the Guinness book of records. As this is more decisive that the runner that Bekele is, a guy that is 5000m and 10000m WR, Olympics and world champ, that can win the world cross country short version ion the evening of one day and on the morning of the next day he wins the long version, How many times ?
In my opinion what would be fantastic is Carlos Lopes for example, that he by the way did win 3 world champ cross country , marathon Olympics and marathon WR and he did fantastic workouts, Why ? Because never did one single 400m faster than 60 secs in training. This is what is fantastic one slower talent that did 27:17 and 2h07:12, not a 26:16 runner if he is able to run 52-54s for the quarter.
Finally I ask myself what is the knowledge of the author of the article, I don´t want to personalize this question, but is this the rich modern science from the author ? He is so analphabet that he can´t see by the look to the graph that the workout is not what he says. I see. This is modern science. Inaccurate date, poor interpretation, added with presumption, misunderstand of the issue.
Ps – by the way, the first 4 peaks of the graph, when we see the HR goes up to 90-100 HRB is just short strides that he did as warm-up before to move up and start the workout. 4X100m strides probably.