-The article has nothing to do with the most effective way to go from a 7:30/mile guy to a 5:30/mile guy.

-These guys are also already running ~50 miles per week.

-Many AG triathletes advocate doing their speekwork/interval work week in week out for many months at a time. This study only did 4 weeks of interval work.

-4 Weeks of increased volume is not nearly enough time. Perhaps you should read Gordo's article on "elite base". The foundation/base we develop today will help us 18-30 months from now.

We swam very little at z5. We swam very little at z4. The vast majority of swimming was done in zone 2, with the end of the workout in zone 3.

The really good guys spent more time in zone 2 than everyone else. Good as in 15:15 in the the 1500m LC and another guy who was 4:19 in the 500 (scy).

There are a lot of programs out there which do too much higher intensity training. Those guys don't have the base. Yes they were fast, but they probably would have been faster if they developed a deeper aerobic base.

Good distance swimmers spend tons and tons of time in the 135-150 zone. Hardly anyone is swimming (among distance guys) is swimming in zone 5 at all. The people who can handle significant time in zone 3 and 4 are the people who have built large aerobic engines over time. This is done in zones 1 and 2.

I would imagine this translates directly to running. In fact, I would imagine runners spend a higher percentage of their time at the lower end in terms of intensity and HR than swimmers do. There is a lot more impact on the road, so you can not spend as much time in z4 when running compared to swimming.

The average AG triathlete is way too lazy to go and run 35-50 miles per week. Take the OP. I would imagine he can run 8:30s pretty easily, or 7 miles per hour. If he is running ~20 miles per week now, then that is about 3 hours of running. 6 hours per week of running would get him huge gains, but most people don't want to try it. Instead, they want to go to the track on Tuesday and do their 400s and 800s. Another day they want to trash themselves on the local evening "roadie ride". While this type of training might be "fun", it is not necessarily going to get them better. They have to decide which is more fun in the end.

The OP should make it his goal to run 50 mins +/- 10 mins 5 to 6 times per week for a number of months. Resist the temptation to go hard. JFR. I would advocate keeping most of this very easy, borderline too easy (zone 1), so he can ensure he doesn't hurt himself with the increase in milege. After 2-3 months of around 5-6 hours of running per week (~40 miles), then see how much of the running he can do in zone 2.

It seems all we have to do to run faster is to run more, it is so freaking simple, yet people love to muddy the waters. Also, if you throw in too much intensity on the track and dont have the base to let your body be able to handle that type of stress from running, then how are you going to recover to give a honest effort in your key cycling workouts without cooking yourself?

Very few people will ever get to running 5:30s in any triathlon, but I can promise you nobody who is running 5:30s is doing it on 20 miles per week. At some point in any 34 min 10K guy's life he did a lot of miles.

Have 10,000 people do it one way, then have 10,000 people do it another. Compare the results. I already have and that is why I believe it. If you really want, I can probably dig up 50 or so specific examples that I'd seen with my own eyes of people who had a high intensity to volume ratio and who went flat or fell apart by the end of their season. Combine that with the fact that every repuatable coach subscribes to the same belief.

Now here's a question for you. Why does so much of the triathlete / running community insist on remaining so damn ignorant despite the boundless amounts of information that one can find in book stores and the internet?

I would submit that it isn't muddy at all, and I doubt that the size of the gains that he made after that "period of unusual intensity" would have been nearly so large if they hadn't happened after several years of huge volume.

Like Flanagan pointed out...the flaw in those studies that were cited is that they only accounted for short term volume. Give me only 4 weeks with someone and I'll pick intensity to "win" the study in nearly every case. Give me 6 months or a year...I'll take the volume and frequency approach.

Bottom line is that the dude doing 20mpw doesn't need to inject intensity to get to 5:30 miles...ain't gonna happen. More volume. More frequency. I just don't get what is so hard to understand about that...except that it is the harder, longer term solution to getting faster...everyone wants to Cliff's Notes their way to speed.

Daniel's programs have a lot of interval work. I haven't read your book, but should we chalk Daniel's up as being ignorant?

What I see SOME people espousing doing miles & miles of zone 2 to get faster. While that works, the science says intensity will work too.

Take two guys who can run 30 min 10K and say a 4:30 mile. One guy got there by running big volume and a sprinkling of intensity. The other guy got there by doing a sensible amount of tempo work, etc., (not crazy high-intensity), and on say half the volume.

Why would the second guy fall apart? Why is there this belief that one's fitness is somehow more fragile if earned via more intensity rather than less?