REACTIVITY
A review of Easy Interval Method, by Klaas Lok, translated by Russ Mullen
Back in the winter of 2002/2003, I was recently graduated and living with my dad. I had a job as a waiter in a restaurant, which kept me busy most evenings but allowed me plenty of time to pursue my first passion: cycling. I had a degree in Sports Science and an intense interest in the training habits of the pros. If Lance Armstrong (at that time the saviour of the sport) was going to spend the winter base training, doing long rides with a heart rate between 124 and 128bpm, then so would I.
I emerged from winter feeling fitter than I had ever been, and ready for the first race of the season, a semi-pro event on local roads. It would be my first big test; I was excited. On the first lap of the 70 mile race a break went away. When I saw one of the big guys make a move to bridge across at the start of a climb, I jumped into his slipstream. I was doing it. We developed a gap on the climb, then crested the hill and turned left onto a wide, fast road, slightly downhill with a tailwind. He dropped down through the gears, balled himself into an aerodynamic tuck and accelerated. I was pedalling as hard as I could, my primitive bike computer telling me we were nearing 40mph, but even while drafting, I didn’t have the power to keep up. The elastic snapped; he rode away and seconds later, the bunch swarmed past, too fast for me to even catch on. I went home angry and disappointed.
Had I wasted a whole winter of training?
Within a few weeks, with more racing and regular interval training I came good and had a successful season, but it was still a wake up call. Base training is only ever the beginning: it’s what you build on that foundation that counts.
Since then I’ve been sceptical of the idea that time-limited amateurs should dedicate themselves to periodization. It was no problem for Lydiard’s lads to submit to a long base period of ‘slow’ miles, followed by a period of bounding and exercises designed to regain speed, but beware: their long slow miles were nothing like as easy as we define easy, but often closer to long runs at a tempo effort. With that in mind I’ve also been sceptical that truly slow running should be the basis of a year round training program, but I’ve never seen a plausible alternative.
Physiologically I understand the theory behind easy aerobic training, and in practical terms, I enjoy training for its own sake to the point that nothing makes me happier than daily, long, slow runs in the forest. But I also enjoy racing, and I’ve come to recognise that there’s no point having a huge aerobic base if you don’t have the skill — and running at speed or pushing a big gear on a bike can be thought of as a skill — to go fast enough to fully utilise that aerobic fitness.
Klaas Lok’s Easy Interval Method turns regular training methodology on its head, prescribing intervals as the foundation of any program for distances 800m and up. Lok was himself a successful athlete in the 70s and 80s. He spent his best years under the tutelage of Herman Verheul, a fellow Dutchman who believed that ‘reactivity’ is one of the prime factors in determining running success. In Dutch, Lok’s book is called the Souplessemethode, where ‘souplesse’ translates to something like ‘suppleness’, but which better describes that effortless, graceful running carriage we associate with the best athletes, and that we experience ourselves from time to time — where accelerations come easy, and running at pace feels natural and easy. ‘Reactivity’ is Lok’s translator’s shorthand for this sensation.
Both Lok and Verheul believed that this ‘reactivity’ is detrained by doing long, steady running, and that it is better maintained through ‘easy’ interval training — fast enough to engage the best running form, but not so hard as to push the athlete over the anaerobic threshold, which naturally makes recovery longer.
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It’s Lok’s belief that the traditional weekly schedule of a demanding long run, an intense track session, and a tempo run, supplemented by easy miles, places too great an emphasis on anaerobic speed sessions that drain the athlete of their ability to generate ‘reactivity’, while at the same time encouraging plodding, easy miles, which serve only to train the athlete to go slow.
Better, Lok suggests, to schedule one’s week around easy daily sessions such as 6x1km, 10x400m, or 15x200m, with regular racing and a longer, continuous fartlek at the weekend. The mileage may be lower, but the athlete’s form will almost certainly be better, and that combination is, he believes, more likely to create good results with reduced likelihood of injury than traditional methods. The technique worked for him, and there are dozens of case studies throughout the book, from elites, to age group record holders, to very normal, everyday runners.
I first read about the book on a letsrun.com forum thread, and although it flew in the face of popular wisdom, the ideas intrigued me. As a 39 year old father of two, who has been training in endurance sports since my teens, I’ve begun to question why I would want to train the same way as a 30yr old Kenyan pro, or a 20yr old collegiate phenom? I have neither the time, talent, or capacity to improve that those athletes do, so why train like them?
Lok doesn’t make this argument, but it strikes me that as teenagers, when we first engage with coaches, the easy gains are to be made by boosting our aerobic capacity with more running. This continues into our 20s and 30s, where we can reach 100 miles per week or more. But at some point, the capacity to continue increasing volume tails off.
Here’s an analogy: when you first hope to buy a house, you save and save until you have a large enough deposit to get a mortgage. This can be thought of as your aerobic base. Once you move into your first place, do you continue saving, or do you look at other ways to increase the property’s value? For some, continuing to save will be effective, but for others, maybe maintaining what you’ve got, while building an extra bedroom, or renovating the yard might increase the value more. So long as you maintain what you have and keep paying the mortgage, is there any need to keep saving, saving, saving indefinitely?
Easy Interval Method arrived at a time in my life where I don’t have capacity to keep saving while maintaining what I have, and adding value all at the same time. I have about 8 hours per week to devote to running and I have to be sensible with how I use those hours. The 80:20 rule suggests we should do 80 per cent of our training at an easy pace, and 20 per cent very hard, but this rule comes from elites. For a professional runner, who might spend 15hrs per week training, 20 per cent at high intensity would equate to 3hrs. The idea that someone who only has 8hrs per week to dedicate to training should follow the same ratio seems mathematically unlikely. Why the percentage and not the absolute value of 3hrs? I wonder if by following the Easy Interval Method, I can safely begin to increase the volume of intensity, without having to increase volume overall?
Since first reading about the book I’ve been following some of the principles, doing regular 200m and 400m intervals at paces roughly corresponding to 5k and 10k pace respectively, and including fast strides most days. I’m now in my second week following the schedules prescribed by Lok. My 10k best is 34:41, so Lok suggests I do 6x1km at paces ranging from 3:55 down to around 3:40. That’s roughly marathon pace down to half marathon pace. Today’s session went well, but I chose to run a little easier than his advised paces, starting at 4.01 and working down to 3:48 with 1km easy jogs as recovery. Typically my heart rate would be in the low 150s by the end of an effort, and in the low 130s by the end of the recovery kilometre. My stride felt fluid and strong, and my breathing remained relaxed. By the time I got home, with a warm up and cool down, I had covered 16km. Easily enough to maintain my hard-earned aerobic base, but with at least 6km at race-relevant paces.
These aren’t new ideas: Zatopek was doing something similar in the 1940s and 50s, and Mihaly Igloi’s approach followed on from that thinking. To this day swimmers rarely conduct long steady mileage swims, but do most of their aerobic conditioning in the form of easy intervals. Swimming is a technique sport, and by splitting sessions into intervals, they are able to ensure their training is conducted entirely with proper technique.
As I get older — I turn 40 in two months — maintaining this connection to the paces I want to run feels energizing. At the same time, losing some of the pressure I feel to maintain, or build my weekly mileage is liberating. The real question I ask myself is how easy will it be to maintain motivation when there are so few pressure-free, easy runs on the menu?
I’m going to follow this program for the summer and see where it takes me. These lockdown days have provided us with a rare opportunity to experiment with our training, and whatever happens, I will feel like I’ve succeeded in some way if I come out of this period having learned something. The main thing, as Lok reminds us throughout Easy Interval Method, is not to push for progress too hard — sometimes ‘easy’ is enough.
I bought Easy Interval Method from Amazon, but it’s also available direct from the author at http://www.easyintervalmethod.com/
