More 3k, 5k, and 10k paced intervals?

10k paced intervals are my go-to for most anything. Do a few of those with some 400m repeats at 3k speed tacked on to the end and ready to rock the 5k.

+1.

I'd add some regular overspeed work, such as strides/wind sprints and hill sprints. A lot of people who are proficient in longer distances (sheepishly raises hand...) find that they develop a gait that is less amenable to the short stuff (often called "sitting in the bucket"). Overspeed work helps correct this.

Fartlek type runs aren't a terrible idea either. 8-10k at tempo or half marathon pace with a few 400m reps at 5k pace should get you used to holding the speed when you are tired without killing you for the next workout.

when you say half pace is that current or goal pace for upcoming race?

Good question.

Steve Magnus at the Science of Running had a good post on this topic. He calls training to run X distance at Y goal pace "specific endurance". Bear in mind that this post is aimed at the coaches of high school athletes, so there's a strong "let's not burn out a kid who only has a year of endurance training under their belt by hammering them" element. The principles are the same, but if you've been doing this endurance silliness for a while, you might be able to transition more quickly, or skip elements of base building.

http://www.scienceofrunning.com/2008/10/hs-trainingspecific-endurance.html

Yeah, it was about cycling. The Senior Games has short cycling TTs - 5k and 10K. I've never done a good 5K TT and I'm trying to put a plan in place to significantly improve my times in both events, but especially in the 5K. I just did a 5K TT (part of the Pensacola Cycling Classic) on Saturday to see where I stand - and I was pretty disappointed.

1. Ride your bike as much as possible.
2. Once a week practice 5k TTs

5k TT is still almost entirely aerobic. Learning to pace it and hurt bad is the main reason to practice it, rather than specific physiological adaptations.

While a 5k has a large aerobic component it's going to be the ability to go anaerobic that will make the competitive difference. I'd REALLY try and buff out my ability to go anaerobic by doing high watt intervals lasting from 1 to 2 minutes. Some with plenty of rest and some with the start of the interval just below 5k race pace. These will be disgusting.

with reference to pacing and hurt bad parts, are, totally things worth practicing, the shorter the event the more important they become.

Old guys rule.

Indeed, I think one of the biggest misconception is the degree to which anaerobic capacity is critical for shorter durations in comparison to aerobic.

Let us do some math using the CP model. Take a hypothetical athlete with a CP or threshold power of around 250 watts and anaerobic capacity of 10 kilojoules

A 5k TT will take about 6 minutes for someone like that of normal size

Assume I work hard on my anaerobic capacity and add 20%, so I am up to 12 kilojoules.

That adds about 5 watts to my 5k TT power (2 kilojoules over 6 minutes)

Conversely if I raise my threshold power by just 5% then I add about 12 watts to my 5k TT power

Obviously the CP model does not perfectly reflect reality, and I may be making an error in some assumptions or analysis here. I would be happy to have feedback.

great points. My mistake was using the term anaerobic when I meant to say threshold (AT). However, the method to get there is still the same disgusting hard intervals. This kind of stuff works great for me anyway, maybe because I'm all slowtwitch and any development of speed/power really hurts - but helps.

Also, given your explanation (which is as usual - good), it seems to me that it would indeed pay to do both anaerobic work and threshold work. But, if one had to go, I'd agree that it would be the anaerobic stuff.

admit it - old guys DO rule :-)