I agree with Orville Atkins when he quotes Igloi and Hungarian training. The TEMPO RUN terminology was early introduced in the distance training methodology by east-europeans up to ex-USSR (Germany, Poland, Hungary, Russia, etc).
The term TEMPOLAUF means fast-running.
What are the characteristics of the TEMPO RUN ?
Before to know what is and what´s the format and what´s the pace, WE NEED TO KNOW WHAT FOR, WHAT´s the target goal of the training that is named TEMPO ?
The goal of tempo run is to create a training stimulus that isn´t aerobic straight (pure steady-state) and that might benefit the distance runner to efficient operation of the systems that do contribute for enhance his shape condition that able him to performance enhance. The goal is that cardio-vascular, muscular, biomechanics and more systems that interfere in the race pace be demanded that was easier to resist to fast pace during the competition you are training for. Therefore, it´s the kind of pace that jumps up to the next level of the benefits of easy aerobic runs. Modern physiology do introduce some terminology and some concepts that might fit into the tempo run definition. The lactate anaerobic threshold, the MAXLASS, the sub VO2max, and also new paraphernalia as it´s the heart rate monitor and that defines heart beat parameters, e that are all physiology contribution to characterize the tempo run, but they are all quite incomplete, because the original TEMPO RUN proved to be effective but defined by EMPIRISM and INDIVIDUAL FEELING.
There, another way to define the tempo run, as anything else in the distance training is to use the pace (per distance) to define what´s the pace training zone of the TEMPO. This also might be pace guide, but fails obliviously as lactate concentration values, or heart beat, or the percent of VO2max, or the pace/velicity of that VO2max percent (vVO” max.) because that doesn´t take in consideration intrinsic and extrinsic factor that might limit the pace or the distance or both of the TEMPO. What´s the training that the run did before the tempo, what´s the temperature and humidity, his he tired, so and so. This are some eros why the ultimate define TEMPO RUN might be done by empirics and feeling/internal load. Might be a initial pace guide, but ther´s nothing as ESP – extra sensorial perception to define the pace and duration of the tempo run.
Now the format of the TEMPO.
Is that a continuous or run by intervals/repetitions ? It´s a CONTINUOUS RUN, not by intervals.
Is that a slow run, typical of easy aerobic pace or it´s a fast continuous aerobic run with some percent anaerobic lactic demand, that your lactate moves up during the tempo run duration ? It´s a FAST AEROBIC RUN WITH ANAEROBIC PERCENT.
It´s a all-flat-out maximal effort/stimulus run at the pace that it´s one distance competition or it´s a sub-maximal run ? It´s a SUB-MAXIMAL RUN. What that means ? It means it´s fast run but if you run one 5 mile TEMPO for instance , the pace shall be slower than that 5 mile.
One important point, that´s why I think that Kevin Beck it´s totally wrong. I guess that the pace of the tempo, the pace speed/intensity, being sub-maximal stimulus, it depends how much distance/how much time duration of each tempo. It´s wrong to define one straight pace for different TEMPO run duration or different distances of the tempo. If you go to run a 4K/2.5mile tempo run, the final part of one training sessions of one hour total while faster the pace let´s say in the final 16-17 up to 20min or so), or if you gonna do a 10mile tempo/17k, it´s obvious that the pace can´t be the same eventually.
One final note. What I understand about Lydiard training, he prescribes something I would define like tempo run, the best aerobic pace, and by what I write ahead this is one aspect that a agree with Lydiard training absolutely, if the Lydiard define what we mean by tempo might be done by feeling and not too much pace (or time duratyion) previous determined.
PACE PRECISE KILLS THE TEMPO RUN.