I noticed this more when I reread his article on how to break four minutes and tried to apply it to a top level guy like El-Guerrouj.
Here is Horwill's suggested training (it must be repeated several times mind you) for someone seeking to go sub-4. Obviously El-G is significantly faster than sub-4, but the argument still applies:
"A programme to break the barrier
We are now in a position to compile a programme based on physiological data to break the four-minute barrier for the mile:
Day 1 - (Aerobic, 80% VO2 max). Run half-marathon distance 64secs per mile slower than for one's best mile time. Example: best mile time 4:10, run 5:14 / mile or as near as possible to this.
Day 2 - (Anaerobic, 110% VO2max). 2 x 1 x 400 + 1 x 800 + 1 x 300, at 15 secs per 100m throughout. Take 30 secs rest after 400m, 60secs rest after 800m and a lap walk after 300m before repeating.
Day 3 - (Aerobic, 90% VO2 max). Run 10km 48 secs / mile slower than for one's best mile time. Example: best mile 4:10, run 4:58 / mile.
Day 4 - (Anaerobic, 130% VO2 max). 4 x 400, 4 secs per 400m faster than per 400m for best mile time. Example: best mile 4:08 (62/400), run 400ms in 58 secs, 3 mins rest.
Day 5 - (Aerobic, 95% VO2max). Run 5 x 1K at 8 secs per 400m slower than for best mile time. Example: Best mile 4:04 (61 / 400), run at 69 / 400 = 2:52, with 60 secs rest.
Day 6 - REST.
Day 7 - (Anaerobic). 1 x 350, 1 x 300, 1 x 250, 1 x 200, 1 x 150. All full out, with 400m walk after each. N.B. Race every other seventh day instead of this session.
On Day 5, alternate this session each week with an aerobic 100% VO2 max session of 4 by1,500m, 4 secs per 400m slower than for one's best mile time. Example: best mile time 4:02 (60.5 / 400m), run 64.5 / 400, with 3mins rest after each.
There is a competitive pattern called 'psycho-logical race preparation'. This is where each month starts with an over-distance race, either 5km or 3km, then an under-distance race, either 400m or 800m, then the specialist distance, in this case 1,500m or a mile. The first confirms endurance, the second speed and the last brings both together."
Now, the first thing I notice right off the bat is Horwill's inability to stop THINKING at times and let the runner go by feel.
Honestly, what runner will perfectly conform to standards of 87.86539% VO2 max pace every day?
Also, he has almost NO days of easy running. On day 6 of the schedule there is complete rest, but after 5 days of track work and hard road work (slowest run being at a still fast 80% VO2 max) a runner's legs would likely seize up without some sort of jogging on grass.
Anyway, back to El-G.
This is what El-G's training under Horwill would look like assuming he followed it to the T (and it seems by Horwill's writings he settles for no less than this precision).
Assume El-G is in 3:44 shape (which he probably is half the year anyway).
Day 1 would have him out for a jolly half marathon jaunt at 4:48 pace, or a 1:02:56 total time (just shy of WR marathon pace).
Notice too that no warmup is mentioned at any point in the schedule, though one must assume he does not recommend springing out the door at 4:48 pace.
Day 2 sees El-G going at 14 seconds per 400 for 2 sets of 400/800/300. This session by itself is not bad at all and likely quite manageable for 3:43.13 miler El-Guerrouj, but the day after a 1:02:56 half marathon it will likely prove a wee bit unwelcome.
On Day 3, El-Guerrouj will head out for a 10,000 meter run at 4:32 pace (3:44 mile pace + 48 seconds per mile), or 28:10. Perhaps Wejo could hop in on El-G's training session and sprint by on the last lap for a PR.
By Day 4, one must imagine El-G is getting a bit tired. Today, though, Horwill calls for 4x400m at 4 seconds per lap faster than mile pace, meaning 52's for Hicham. After a hard half-marathon, 10K, and 400/800/300 session in the last 3 days, El-G might have some problems with this one.
If Hicham can walk the next day (Day 5), he will head to the track again for 5x1000m at 8 seconds per lap slower than mile pace, for him 64 seconds per 400m. He would do 5 1K reps in 2:40, or 13:20 5,000m pace. If he has not popped an Achilles tendon by now, he should be fine.
Only the Lord knows what El-G would choose to do on Day 6, his rest day. Perhaps he would hire a masseuse for a 6 hour session at the table. Maybe he would make an emergency flight over to Ireland to see Gerard Hartmann. Perhaps he would not even wake up out of his bed at all during the day. Perhaps, perhaps, perhaps... as Chris Lear said, it is a futile game to play.
Still, the next day El-G's rabbits will drag him out of bed and to the track for some flat-out reps of 350m, 300m, 250m, 200m, and 150m. If I was a betting man I would put some money on Hicham's hammys failing today.
Nevertheless, the next day he would be back out the door for a 1:02:56 half marathon and a repeat of the last week again and again. Again, we must assume his blood pH remains less than that of hydrochloric acid to surmise that he will race the odd mile or 1500m every other week on Day 5 as Horwill suggests.
There you have it boys and girls. Try this one out on any world class athlete or yourself and see if you will last.
My guess is you will not.