DIARY: First Interval Session

As a runner, it pays off to face the facts about yourself. Telling yourself you're the best thing to hit running since William Kipketer is all well and good, but the stark truth will still catch up to you when you hit the wall during some race out there...

So my first test with the Peak Centre confirmed what I had always suspected: I'm slooooow...

Sure you can put me in a company football side against a few average Joes or sedentary chair-huggers and I'll look all Speedy Gonzalez, but I've seen my impact wane the second anyone with real pace is given a go against me, in any team sports.

Emma Watts of the Peak Centre has the cure: the old method of "interval training".

I did my first session today, and can attest that it'll make you instinctively prepare to catch your lungs, should they pop out from sheer over-use. Given how terrible I felt throughout, I have no doubt, it'll work. But what is intervals, and why do it?

Interval training is really not rocket science, its any type of running were you will wary your speed and effort from one time interval into the other. For instance, 2 minutes slow running, 1 minutes sprinting. As simple as that.

Out-of-shape runners should experiment with longer intervals first at lower intensities broken up with longer resting periods (say 3 minutes fast running, followed by 6 minutes of slow jog or total rest).

Competitive runners, will have to look at exactly what region of the Heart Rate Zones they want to work on. The target? To increase your base speed at any given level of exertion. This is what Dennis Dreyer refers to as a Perceived Effort Level (PEL). When I'm perceiving myself going a the maximum I can now, I'll only be hitting around 16kph for any significant amount of time. With proper interval training, I'll still feel just as awful (the PEL will be the same), but my speed might increase to 18 or even 20kph.

Choosing Your Intervals - The Science Behind
Every runner has different gears, the speed in each gear differs from runner to runner, but the exertion would be much the same. When I'm running at my max., the best consistent speed I could clock up over a 4-5 minutes would be 16kph. Garry Crossan would probably clock up 20kph without pushing himself further than me at all.

We must therefore identify what we want to improve (we'll look at specialised speed exercises another day). Today, we'll talk intensity, and my performance suffers most when I enter the HR zone called MAC (Maximal Aerobic Capacity). This zone is different for everyone, and you'll need to get a physical test done to find yours. If you need a rule of thumb, I'd say take your maximum HR (220 minus your age if you cannot get a precise measurement done) and find 95% of that value. That range will be close to your personal MAC.

For me the zone is any exertion that forces my HR up to 184 to 193 bpm (beats per minute). I usually enter this zone for brief spells during races, but am generally limited to maxing out in the zone below (called the 2nd Anaerobic Threshold, or AnT2, 177-183 for me).

From the data we analysed from my treadmill test, there is a clear spike when my speed increases from 14kph to 15kph. Before this increase the lactate levels have increased in small equal proportions. This means that this is the limit of my current performance and when I try to push beyond, I get in trouble fast. This is why I always fade on the really steep hills during races, losing minutes by the bucket in the process. By working on this specific area, significant speed gains can be achieved.

So why do I get fatigued quicker in this zone than in the others? What must we fix?

The basic answer is simple, your bodies ability to supply energy has reached a level where it is failing. Many believe this to be down to a build-up of lactic acid in the muscles, created as a by-product of burning mainly carbohydrate as fuel. This is a myth. To fully grasp the essentials of this before proceeding please read my "Article: Physiological Myths I: Lactic Acid & VO2 Max" that I'll publish in the next few days...

If you don't care about the science, but will take it on blind faith that interval training works, please continue reading...

Choosing your Interval
Since I know that my weakness lies in the very high-end of running spectrum, I must choose a particular type of interval training. Like many competitive runners, I have excellent base fitness, but my ability to handle high speed running or extreme exertion such as very steep ascents, is not sufficiently developed.

If you are having trouble when your heart rate is in the AnT and AnT2 (Anaerobic threshold, remember?), the best way to strengthen them is by pushing you MAC (Max Aerobic Capacity upwards). By pushing the top of the bar, everything below it follows it up. Seems logical no?

Since I race most races at a very high intensity (183bpm on average), only work at the very top will have an effect. So to this I must force myself into the range of 184 to 193 bpm during the intervals.

The more intense your intervals are planned to be, the shorter they will also have to be (unless you're a machine). In normal interval training running at 3-5min at high speed and then 3-5min at a lower speed is perfectly fine, but for anyone who, like me, must work on increasing their max performance output, we'll have to use ultra short intervals.

The main goal when working in the area of your MAC is to increase your VO2 max. as well as your power output when reaching your current VO2 maximum.

Today's Session - 1min/1min
When doing intervals, you either need a track (thus breaking you intervals into distance, in the form of laps, instead of time), a fixed point to return to, or a good watch.

My Garmin ForeRunner 305, comes with a fully fledged interval work-out, so all I had to do was programme in a warm-up, my interval time, my rest time, my cool down, and the number of repetitions (reps).

My program looked like follows:

  1. Warm-up (the run to the park I had selected)
  2. 1 minute intervals
  3. 1 minute rest time
  4. 20 repetitions
  5. Cool-down (run home from the park).
I choose a good park nearby with a rounded track around the grass, so I wouldn't have any disturbances in my way when trying to hit top speed. This is how it went...

Boring! Variations please, or where do my mountains come in!!!
A few variations exist, most notably the Swedish "fartlek" (speed-play) which is practised by picking a fixed location in front of you, sprinting like a madman t'wards it, and then jogging to the next fixed location in front of you. Simple really, thus "play"...

For the real masochists and madmen out there, fell-drills is the only way to go. As the Spartan guru Anthony Bova was once quoted as saying (I recommend checking out his site here): "Run hills, preferably with weight on your back, and you'll look like Hercules in no time". So why not make that even worse and do it as intervals?

Richard Askwith describes this technique in his book "Feet in the Clouds", and its basically hill running with 90 seconds of full on, burst-your-lungs running, and then 90 minutes of slow jog (up the mountain though!!!).

My personal variation, call it the "Fell-drill for City Slickers", consists of picking a hill in or close to town: It should be at least 100m, preferably 200m in length, and have a good solid ascent grade. Then set your timer to a set time (I recommend 20 minutes for the first time), and sprint to the top of the hill at your maximum speed. Then walk down slowly again, and, with no further break, sprint back to the top.

Once your fitness improves, stop walking down, and do a slow jog down the hill. Eventually you'll be able to do normal running down, sprint up, normal running down etc. If you cannot find a suitable "painful" hill, here's another trick I use: Take one of the 5l water bottles from Tesco, fill it up, and stuff it in your backpack, then complete the Fell-drills as described above. If that won't kill you, nothing will (well, maybe more weight!!!).

Results - Wide of the Mark
My programme turned out to be way too optimistic. You have to stop your interval session once you can no longer maintain proper form during your intervals of maximum effort, and today I had only enough in the tank for. Another great feature of the Garmin is, of course, that not only does it give you the reminders you need to keep your intervals perfectly timed, it also records it all in the proper format for later analysis.

I did 1.45km of normal running as warm-up and a 1km jog as cool down. In the middle of that, I managed to crunch out 12 hard and fast intervals and just as many slow jogs as my "rest" in between.

My speed was not impressive, but I was fairly consistent, doing between 0.2km and 0.26km per minute during the sprint intervals, producing a max speed of 19.8kph at my best.

I could not push myself as far as I wanted, however, during no single session did my average HR get higher than 178 (to do MAC training my average needs to be a minimum of 184, so I was practically doing AnT1 and AnT2 training, which has many of the same effect, so is not a total loss). My max HR was 189, which truly shows how hard mountain running is, as I get up to 193 at some stage during most my races.

Planning the Next Interval
Today's interval gives me a baseline to work with. In order to enable me to run faster during the intervals, and get closer to the MAC, I'll increase my resting time to 2 minutes, and then try to really hit it, during 1 minute of sprinting.

Also, its very possible that my low speed on the flat will simply prevent me from pressing myself to the limit for the beginning, so my plan going forward will look like this:

1 x Normal Intervals per week (1 minute sprint/1 minute rest)
1 x Fell Drills (1x Weighted Uphill Running/1 x Downhill Slow Jog)
Increase intervals with 2 per week (in my case from 12 to 14 etc.)

Sprinting up an ascent with a rucksack and 5 kilos of water, should push me closer to the 193 bpm, and eventually my goal of becoming a faster runner who will not fade so quickly on the steep hills.

Food for Thought - Keep it Steady
Today's result confirms that I get exponentially more and more inefficient, the harder I push myself.

I accidentally cross-checked today's reading against my 20.82km run on Saturday, and for both activities I had the same average HR (159bpm). Yet my speed during the intervals, a measly total of only 7.2km or just over 33% of Saturday's distance, was only 20 seconds quicker per kilometre! Now this can be contributed to overall fatigue (which is unlikely since I only did light weight-training on the Sunday after).

Instead it shows that running at my max takes so much out of me, that I cannot sustain a good pace at all until I've recovered. In other words, if I was only a road-runner, I would have to search for an optimal pace, and then work towards getting that moved up slowly.

Mountain runners don't have this luxury, as we can be forced into these uncomfortably harsh PELs by the next mountain being thrown in our path. But it still serves as a warning not to push to hard during races at certain stages. Keeping a slightly lower speed the whole way through, could get you further up overall, than pressing yourself 100% at other stages.