I’m about to tell you about one of my absolute favorite workouts because it is so darn effective at making people fast at running.  It’s a variation on a running workout that came out of some research about 14 years ago and it’s amazing.

Billat Intervals

I’m an old guy.  And I’m a geek.  Way back in 1999, I was reading the March copy of Running Research News and was astounded by an article describing the work of Veronique Billat.  This article created an enormous stir in the running community over the next few years because it proposed amazing physiological adaptations from running at your maxVO2 pace for just 30 seconds!  Well, not just once– 30 second repeats over and over each separated by an equal amount of time of jogging.  The benefits improved even more as one reached longer intervals– up to three minutes long.  You can get a good sense of what these workouts look like by reading about it in this article by Owen Anderson— basically, they are hard intervals that last either 30 seconds, one minute, or three minutes with equal recoveries.

A couple of days ago, I talked also about the real importance of lactate threshold in your race performance.  While it’s hugely important to improve it, polarized training just says you don’t want to train there— instead you want to train a lot faster.  Think of this as pulling up lactate threshold from above instead of pushing it from below.  It just so happens that maxVO2 is another physiological variable above lactate threshold that we can use instead.  While trying to improve one’s maxVO2 may seem to be a less-than-worthwhile effort (it correlates with very little in terms of predicting race performance), it turns out that knowing your speed while at maxVO2 is a pretty worthwhile thing to know.  And it’s also relatively easy to guesstimate– just figure out how long it takes you to run 6-minutes all out.  Because runners like to use distances, this 6-minute figure comes out handily for me because my mile time is just a shade faster than 6:00.  Voila, I have a ballpark pace of VO2max (actually, the literature uses vVO2max as “velocity at maxVO2” but who the heck plans their running workouts based on miles per hour other than diehard treadmill runners).  The great running coach Steve Magness has a lot of doubt about the benefits of pinning magical success on vVO2Max, but the point isn’t the number– it just happens to be a line in the sand that we can use.  It’s a convenient measurable number that we can use that happens to be above lactate threshold.

So let’s assume Bob has a mile best time of six minutes (happens to be a convenient number).  We won’t care if that’s exactly his VO2max pace– let’s just pretend that it is.  To do a set of one-minute Billat intervals, Bob would run a minute at 6:00 pace, jog a minute, and repeat until he can’t run a minute at 6:00 pace.  If Bob was running on a treadmill, this is really easy to figure out, but if Bob was running at a track, one minute at a six-minute pace comes out to 266 meters– no exactly the simplest distance to run!

First Improvement to Billat Intervals: Stick with 400 or 600 Meters

A better way for Bob to run his Billat intervals is to forget about running 1:00 at a 6:00 pace (again, unless Bob is running on a treadmill).  Instead, a better way for Bob to run is to run one lap (400 meters) in 1:30, jog 1:30, and repeat until he can’t run a lap in 1:30 anymore.  At the end of each recovery, Bob just needs to make a mental bookmark about his location on the track and run a lap from there (actually Billat’s original research had her subjects jogging at half the speed on recovery intervals– exactly one half a lap if using 400m intervals).  As it turns out, the recovery speed doesn’t have to be exactly half the speed on the recovery intervals, but it is very convenient to start there because it makes remembering where to start and stop much easier.

Second Improvement to Billat Intervals: Changing Up the Recoveries

After Billat’s influential (but controversial) research, another French researcher (Delphine Thevenet) asked whether jogging (active recovery) was really necessary or produced better results than walking or standing still (passive recovery).  In her research, she showed that runners doing the 30-30 Billat intervals who engaged in passive recovery between each interval were able to run twice as long by using passive recoveries than active recoveries.  While time spent at maxVO2 is likely the key determinant of success, this would seem to suggest that passive recoveries are much better.  However, in terms of oxygen consumption, the runners using passive recovery spent about the entire first half (15 seconds) just getting up to the same level of oxygen use as those that engaged in active recovery.  In other words, there was absolutely no difference in physiological benefits for the two groups.  But the physiological benefits are only one side of the equation– their are also neurological changes (in terms of running economy and muscle recruitment) that are improved by additional high speed running (favoring passive recovery).  On the other hand, more high-speed running also means greater risk of injury (favoring active recovery).  All of this is important if you are trying to decide what kind of recovery you should be doing in your interval training.

With that aside out of the way, I found an even better way to combine active and passive recoveries for Billat intervals: start with active recovery (jogging) and move to passive recovery (walking or standing still) when I can no longer hold the proper pace during my Billat intervals.  Using this strategy, our hypothetical runner Bob (who can run a 6:00 mile) now does the following workout:

1. Bob runs 400m in 1:30 (Bob’s one-mile pace)
2. Bob jogs for 1:30 (equal running and jogging time)
3. Bob repeat run/jog sequences in steps 1-2
4. When Bob can’t run 400m in 1:30 anymore, Bob walks the 1:30 recoveries instead of jogging them.
5. Bob repeats the run/walk sequences in steps 1 and 4.
6. When Bob can’t run 400m in 1:30 anymore, Bob walks 1:30 even slower or just stands still for 1:30 during his recovery.
7. Bob repeats the run/walk-stand sequences in steps 1 and 6 until he just can’t do a 400m in 1:30

By changing up the recoveries, I think Bob gets all the benefits of both passive and active recovery.  Bob gets much more volume and neurological stimulation than if he stopped at step 3 (when he can’t hold 1:30 for 400m after jogging).  But he doesn’t run quite as long in total as compared to starting with passive recoveries, thus limiting his overall risk of injury.  Cool, huh?

If you wish to do this workout yourself, you just have to know your mile time and divide by four– this will give you your quarter-mile times to substitute in Bob’s formula above.  For instance, let’s say that your best mile time is 10:00.  Then your quarter-mile time at the same pace is 2:30.  All you have to do is substitute 2:30 for 1:30 in the Bob’s numbered workout plan to make it your own.

Observations

Earlier this week, I proposed doing this workout while I was an impromptu substitute coach for the night.  I virtually had a rebellion and everyone went off and did something else.  Substitute coaches get about as much respect as substitute teachers.  I agree that this workout is not for the faint of heart.  At the same time, for the level of benefit, the workout is surprisingly merciful.  And it fits beautifully into a polarized training program and likely brings with it huge MCT-1 improvements.

Now if you remember in an earlier post I mentioned the huge benefits from doing eight-minute intervals at 90% VO2max.  That might be true, but I really believe that it’s important to stress a number of different paces than just 90% VO2max.  Billat intervals are much closer to 100% VO2max, which is exactly the point.  In fact, it’s seeming contradiction between Billat’s work (100% VO2max) versus the other research (90% VO2max) with each claiming the superiority of their methods that leads me to be skeptical of any one magic bullet for intensity.  That’s another reason to just relax about knowing the exact VO2max pace– just use a mile and call it good.

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