Recently, I posted about how I have been gradually focusing on longer intervals– combining the funnel periodization ideas of Steve Magness with the above-lactate-threshold ideas of polarized training identified by Stephen Seiler. This means lots of longer intervals at very high intensity. In a race, of course, this would come naturally. But in training, it’s hard to get the brain to accept the idea of running this fast for this long– unless you fool it. That’s what this short post is all about.
Fool the Brain with Broken Intervals
If you’ve ever been in an indoor cycling class for an entire winter, you have probably experienced the “broken” interval format. Basically, the idea is to give you body a super-short recovery– only about 15 seconds– in the middle of a much longer effort. To the body, the 15-second recovery is almost meaningless. But, to the brain, 15 seconds can feel like a tropical island in the middle of an ocean of pain. Oddly, I hardly ever see this kind of workout in running workouts even though it’s quite common in indoor cycling workouts.
Recently, I had the opportunity to test out this style of workout with my team. I had a really painful workout planned. We had run a set of four hard mile repeats on just two minutes recovery the week before. I told them that they should hit these 1-mile efforts really hard– about 5-K pace. As this is a pretty hard-nosed group of triathletes, they did exactly what I asked– they hit the workout hard. Then, for the next week, I wanted them to keep up the same intensity for three 1-1/2 mile repeats but I didn’t want to give them more recovery. Yes, I know, I’m a very evil coach. I knew that they would naturally slow down because of the longer distance, so to prevent that I told them to break the 6 laps into three sets of two laps (800 meters) each run at the same pace as last week but to take a 15-second break at the end of 800 meters. Most everyone was able to keep the same pace but they most also noted that it was a much harder workout than the previous week.
So how were these athletes able to take a tough pace and run 50% longer the very next week? Six laps (1.5 miles) is a really long distance to run at 5K pace in training. Of course you do it in a 5K race, but it’s hard to do in training on short recovery and for 50% longer than race distance (three intervals of 1.5 miles is just a little less than 50% longer than a 5K). The trick is the 15-second break– it makes us think, “two laps is easy” and we just run it really hard. Then we stop, walk immediately back to the start line, and hit it again. In reality, 15 seconds is nothing and has hardly any physiological penalty.
Perfect for Longer Above LT Intervals
Broken interval like this isn’t for your typical run of the mill workout. For instance, in a 20-25 minute tempo run, I’d never do it. These workouts are typically run right around lactate threshold (one-hour race pace) and one of the key benefits is developing the steady state feel of this effort level. But once you get a distinct notch above LT and get into workouts in the 20-30 minute race pace range, the equation changes. At this effort level, you’re burning up energy at an unsustainable rate and running long intervals that come close to 20 minutes is insanely hard in training.
Unless you fool the brain. And, again, this is where a little psychology and 15-second recoveries can work miracles. This is a really good thing because training at above lactate threshold is exactly what it takes to really nudge LT higher and higher. It also is critical in a good periodized training plan.