NYTimes blog has summary of rat data as well limited human data on endurance
benefit of short (very short, sub minute) intensity training.

http://well.blogs.nytimes.com/2009/06/24/can-you-get-fit-in-six-minutes-a-week/


--- In NYDoubleCentury@yahoogroups.com, Bruce Wells <bkwells@...> wrote:
>
> Tom,
>
> Sounds about right. I think 50-60 miles is a good distance in general for a
> ride. 66 miles is 1/3 of a double. A riders tend to do 60-65 on a normal
> basis, so they tend to be ready for a double by default.
>
> Bruce
>
> On Wed, Jun 17, 2009 at 7:26 AM, T. Nee <nee.t@...> wrote:
>
> >
> >
> > Bruce,
> >
> > Very much in agreement with the train hard on shorter distances for one
> > shot double. The people who go on to do the ultramarathon things, like
> > several centuries back to back or doubles back to back or triples would have
> > to consider the longer distance hard training. My riding group 25 years ago
> > would use May doubles (at 20mph averages hanging for dear life behind tandem
> > trains)to train for ultradistances in the summer, and back to back centuries
> > on late March-April weekends to prep for early May doubles.
> >
> > That all said, your ramp up program is very well done for a mid June double
> > and a world where there's still snow on the ground in March.
> >
> > Having ridden both B+ and B's (mostly the latter in recent years), I think
> > that the B's who want to do the double need a different type of ride
> > schedule than what gets posted on our ride calendar.
> >
> > Thinking about being comfortable with 100+ milers by end of May, B riders
> > should leave April with being comfortable with metric centuries and in May
> > work on their ability to ride metric+ with minimal stops and with tempo. To
> > do this, the April rides posted for B's are about 10-15 miles short.
> >
> > In planning the ride calendar next Spring, perhaps there could be two
> > tracks of B level rides - the current type with 40 milers and another track
> > with 50+ milers leading to 60+ milers. That is, two B rides in the same day
> > at the same time aimed at two different rider objectives. By the time the
> > double training series 75 miler occurs, B's wanting to do the double could
> > have a strong base of 50-60's under their belt, with the latter ones ridden
> > at tempo with minimal or no stops (first stop on the double is at 60 some
> > miles, no?).
> >
>