How long per run do you need to run to make double running days effective?

4 miles or 25 minutes

NewbieRunnerGuy wrote:

See topic question...

They become effective as soon as you get out the door. Search the forum for descriptions of Jim Spivey's training, for example.

I did a triple a couple weekends ago. First run was just for form, second run was AT, third was a tempo. Each run was at least 25 minutes.

But everyone's different. Intervals just wreck my body for days but all other forms of speed work I respond well too.

I gained substantial benefit from 20min morning runs. (And no, they weren't four miles!)

CycloneAlum wrote:

4 miles or 25 minutes

Which one?

I'd look at it like this:

In an ideal world, you have a nearly infinite capacity to recover from big sessions. To get the most out of the mileage you're doing, you do it all as big singles, which confer a bigger training stimulus and thus payoff in terms of aerobic development. All things being equal, if you could manage to run the "maximum amount of mileage" x at y pace in singles, you should do this over splitting it up.

In the real world, your mileage ceiling for big singles is much lower than your mileage ceiling for doubles at a given pace, especially if you start doing workouts. So whatever your maximum amount of mileage on singles is, you could probably run a bit more if you doubled, and thus probably confer additional benefit. Doubles are also useful if you have work/school and cannot allocate 2hrs straight on either end of the day, or are tapering/recovering (and would like to lessen the load a bit).

I would imagine there is a point in the realm of low mileage where doubling, in spite of it allowing you to run more might not be beneficial. For example, it might be more beneficial to run 60' singles consistently over doing 25'/40' doubles if you are looking to build aerobic capacity.

For myself, outside of tapering I wouldn't consider doubling unless my total daily volume is going to be >80', at which point I might do a 30'/50' double. That said, I was once strapped for time and did a very high mileage week in singles during my summer build, and it didn't kill me (though I'll admit it was likely unsustainable for me long term).

A mile, initially.

I'm a big fan of double workouts.

The point of doubles is to run less and have structured, high quality workouts.

As important as the doubles are the recovery is as important.

I agree with what youre saying, but is there any research actual personal experience on the topic for lesser mileage... Say, 65 to 75 mpw?

In Daniels Running Formula he says if you spend more time changing and showering then the run isn't worth it.

"In an ideal world, you have a nearly infinite capacity to recover from big sessions."

You realize that this is not true in the real world but it is not true in any idealized form of our world either. Did you even think about what "infinite capacity" means?