Great Article Jason, At the begining i though it was going to be one of those 'You dont need to do ANY Aerobic work, just High Intensity Training' sermons. But it presents a well belanced summary. In my interpretation its not saying you should not do LSD, its also not saying you should just do intervals, its saying do both.
"I have found the bigger the base, the faster I am able to go in my speed sessions and the better racing season I can have," says Erholtz. "Once the endurance is there, begin to add some variety in the form of speed." My interpretation of what he is saying, is build an aerobic/endurance base, then sharpen with more varied workouts heading into the race season... exactly what i do.
"A study published last year in the British Journal of Sports Medicine compared the effects of long, slow distance training to high-intensity interval training. One group was prescribed six intervals of two minutes each to complete three times a week, while the other group did 60 minutes of slow, continuous running five days a week. After six weeks, the results were conclusive: the interval-trained group showed significantly more improvement in VO2max, despite the fact that they ran fewer days."
Ofcourse a study like this will show that the group doing the intervals improved the most, Anaerobic condition responds quickly to training. When i only have 6 weeks to my next 'A' race then my training also switches to concentrating on Anaerobic improvment. However for an 'A' race i usually have at least a 4 month buildup, for Boston this year i started in Nov. Saying that this study shows that Interval training is more effective than LSD (btw, can hardly call 60 mins LSD) is misrepresenting the situation, all it shows is that Intervals will give the most improvement over a 6 week period.
FWIW its just as easy to perform studies that show that LSD is more effective than Intervals.... and there are im sure hundreds of studies that do just that, and they are equally misquoted and missrepresented in other articles.
One really good point made was that in a trail ultra you will have periods of faster running and periods of slower running (even walking) IMHO it is necessary to train at all of those different speeds, both the fast sections, and yes even the Walking.
One final note. I think it allways makes sense to know exactly what training effect your trying to achieve with each session, if the session is supposed to be developing your Aerobic base then whats the point in running fast up the next hill? however if the session is supposed to be developing the ability to switch speeds on tired legs, then running fast up the next hill at Km 40 might be just the thing.