20x400m w/ 30sec recovery

I've never done it, but it sounds like a good 5k pace workout.

hey, that's a pete magill workout. He says do it at 5k 'effort'

http://www.runnersworld.com/race-training/solving-5k-puzzle?page=single

There is one exception to the off-track rule. As race day approaches, some runners like to add a couple track sessions (also at 5K effort) to "sharpen" their fitness. This isn't about testing pace. It's about solidifying our stride efficiency at 5K effort. While adding hills and turns and uneven terrain has prepared us for actual race conditions, doing one or two training sessions on a perfectly flat surface helps to hardwire the relationship between stride efficiency and 5K-specific endurance. Two workouts I recommend for this are

* 16-20 x 400m (100m jog recovery)

* 6-8 x 1,000m (400m jog recovery)

So it seems the pace run throughout this workout would translate to 5k race effort? I wonder has anyone had experience running this workout and how did it factor into your training?

I run something similar with 1min to 1:30 rest (200m jog usually), depending on where I am in the season and what pace I am running it at.

If I run the 30s rest workout, and I want to run a 25:00 8k. 5min/mile pace to make it simply. 75s for each 400m.

I would say that may be close to indicative for an 8k. It all depends on the runner too. Some people can thrive off of short reps like 400s and recover quickly, but when it comes to running that all continuous, they have no chance.

I usually do it early in the season, to help get my racin' legs back.

it's a good way to do a lot of time at 5k pace without trashing your legs. It is pretty easy to run at 5k pace for 400 meters. They don't even tire you until you are half over.

It is actually one of the workouts i recover most quickly from,because the reps are slow and short. and 5k pace doesn't seem so intimidating afterwards either.

I did 25x400 with 30 second recoveries (switching direction on the track for each rep, which also helped me keep track of "odds" and "evens") two weeks before a season opening 10k last year. I comfortably averaged 85.6 for the 400s, feeling like I had several more reps in me at that pace had I continued.

I ran 35:57 for a road 10k two weeks later without wearing a watch. The workout was almost an exact predictor for me. I am not sure I could have survived that workout at 5k pace. 20x400 at 8k pace would probably be another sweetspot.

Da Costa quarters.

Former marathon WR holder Ronaldo Da Costa was said to do 400s with short rests - sometimes 15-20 seconds. But the general format of high density repeats (run time very high in relation to rest time) goes back many years before that. Back in 1975, I got a workout from Frank Shorter which consisted of 12 x 880y plus 12 x 440y with 50y slow jogs as recoveries. And there are stories that indicate the same concept predates that.

Don't try to hit a certain time on them. In fact, don't even time them at all or you'll either push too hard or you'll get an over-inflated sense of what you could do without the rest periods (even that short a recovery does make it surprisingly easier than a continuous effort). Just run them under control without the pressure of time constraints, slot into a rhythm and use the minimum amount of rest needed to run the next rep at basically the same speed and with basically the same effort, but ideally you'll choose a speed that requires a gradual increase in effort as the workout progresses and leaves you fatigued in a pleasant, trained-not-strained way. This should be a pace that would be moderately tough to hold for the same overall distance with no recovery periods. It's by accumulating more time at a given pace without a marked increase in effort or risk of excessive impact stress that economy at that pace is improved. That's one of the underlying rationales behind interval training.

i did this last XC season. 20x400m with 100m floats. the 400s were around 8k-10k pace and the 100m floats were moderate, maybe 6:20 pace compared to a 5:35 8k pace.

it totalled to be 10k on the track, 25 laps and my time was a 10k PR at the time although i could have run a minute faster in a race. something like 36:15 for the workout

Would you guys think this type of workout would fit well into half marathon training?