Hills or 400s better for speed?

400s do not help your speed. Sprints of 50m-200m will help your speed. What difficulty did you have with 200s?

If you're really interested in developing leg turnover, that's more of a neuro-muscular issue that can be addressed by doing downhill sprints (~-1% grade).

If you're interested in applying a more powerful force, then use the hills.

If you're interested in working the anaerobic system, speed endurance, then do the 400s where you can keep the rest short enough to feel the burn.

I doubt you're really interest in leg turnover if you're primary interest is the 5k. If you want to peak in 6 weeks, then I would put the emphasis on speed endurance rather than power and do the 400 repeats with short rests - 4 sets of 3 x 400 @800 pace with 1:00 recoveries and an 800m jog between sets.

Note: I think there are probably many other workouts that would be more effective at maximizing your performance in a 5k. I wouldn't put an emphasis on any of these workouts for a 5k.

Another Option wrote:

If you want to peak in 6 weeks, then I would put the emphasis on speed endurance rather than power and do the 400 repeats with short rests - 4 sets of 3 x 400 @800 pace with 1:00 recoveries and an 800m jog between sets.

Surely even 1 set of 3 x 400s at 800 speed, with only a 1 min recovery is hard enough. But 4 sets with an 800 jog rcovery in between - you're kidding right? Running a total of 4,800m, or 3 miles, at 800 speed in the session?

Another option, what workouts would you put an emphasis on just out of curiosity? I've always felt its very important to train at race pace and as more of a distance oriented runner than speed tempos have always been a staple of my training. Also, I do agree with Karma police 9 400s at 800 pace seems nearly impossible. Are you sure you don't mean mile pace?

The total volume of the workout should be determined by your own capabilities. When you can't hold pace anymore without great struggle, the workout is done. The example workout I gave would certainly be tough, especially for a speed oriented runner.

Your initial message gave me the impression that your speed isn't close to your endurance, which means you would be more likely to hold onto 400s at 800m pace than a miler would.

Nevertheless, the point is to highly stress your anaerobic system, let it recharge, then hit it again. The 800 jog in the middle can be a slog. The point is to recover to the point you can repeat the next set of 400s like you did the previous set.

You could also run 300s instead of 400s as long as they are long enough for you to feel the burn the last 50-100m.

Give yourself a full two recovery days afterward before trying another hard workout.

...But as I said, I would bother with this if I was trying to peak for a 5k, especially if speed wasn't my strength.

As a general philosophy, I believe that you should work on weaknesses early and focus on strengths late in your total training cycle. In other words, do hills, hill sprints, downhill running, bounding, fast 400s with big rest, late in base phase and early pre-comp phase (assuming ~6 weeks/phase) since you consider speed a weakness.

It's kind of foolish to try to put together a plan for an athlete I don't know, but see if this sounds like it might work for you:

If I were coaching a runner like you (or at least one that is more endurance-based than speed-based), six weeks out from your goal race, I would have one workout each week done at VO2max speed. Earlier in the season we would do these with equal run-rest ratios, but six weeks out we would begin cutting these down so that if we were doing 5-8 x 1000m repeats we would cut the rest down to 2 minutes rather than 3 minutes. We would also have one tempo workout lasting 25-30 minutes at current 5k-pace + 20-30 seconds. Add in 2x400 firm immediately before the tempo run. Cut your long run back to 20% of weekly mileage and make it progressive, so that the last 1/3 is very firm. On the easy days after your aerobic run, do 4-6 x 20 sec firm strides (800-->400 pace).

Three weeks out from your goal race change the VO2max workouts into race simulations. Break 5k roughly into 3 pieces with 1 minute breaks/1000m run: 3 x 1600 w/1:36; 2x2000 w/2:00 + 1000, 3200 w/3:12 + 1200 w/1:12 + 600, etc. Drop the 400s before the tempo run, decrease the duration to 20-25 minutes and increase the intensity by running at current 5k pace + 15-20 sec. Keep the progressive long run, but keep it under control - just run the last 3-4 firmly and keep the rest of it at a good training pace. Keep up the strides, but you might want to change to 3x300m strides at 800m pace to develop the fluidity you want for a strong, long finish.

The last week, I would do a 1600m TT on Mon, assuming a Saturday race and a 3 mile tempo on Wednesday. Keep everything else the same; though, save the progressive run and make it a nice long recovery run the day after the race. Don't drop significant mileage unless you are a high mileage guy. If you're running less than 50 mpw, I wouldn't drop below 40 mpw.

Karma Police wrote:

Surely even 1 set of 3 x 400s at 800 speed, with only a 1 min recovery is hard enough. But 4 sets with an 800 jog rcovery in between - you're kidding right? Running a total of 4,800m, or 3 miles, at 800 speed in the session?

You are correct; though, I wasn't intentionally kidding. I was mixing two different workouts. A traditional miler workout we often do 3-4 weeks from the end of the season is 10-12 x 400m w/1:00 at goal 1600 pace -tough but "doable". An similar 800m workout is 3 x {2x400 at 800m pace w/1:00} with full recoveries between the sets.

As I mentioned, I don't think any of these would be optimal for the last 6 weeks of a 5k preparation cycle.

Another Option wrote:

... Keep everything else the same.

By this I meant keep your easy days about the same - an aerobic run + strides.

Another Option wrote:

The total volume of the workout should be determined by your own capabilities. When you can't hold pace anymore without great struggle, the workout is done. The example workout I gave would certainly be tough, especially for a speed oriented runner.

This is a fair point. A speed orientated 800 runner wold find that session a lot tougher than an endurance based one.

Forget 400 repeats - no help whatsoever in developing speed. Shorter uphill and downhill sprints can be beneficial - but not 60-70 secs. Should be no more than 10-20 secs. For the track, I would recommend a workout of something like 3x150, 3x100, 3x50 at 90% effort.