Back after the intervals

Interval training for distance runners


Interval training can be an extremely effective technique for improving your running speed. However, a common misconception prevails: they are only used to sharpen speed during a ‘peaking’ training phase. Interval training works both the aerobic and anaerobic systems. Utilised with care, running intervals early on in a training plan and at the correct pace can increase your lactate threshold, enhance your body’s ability to deliver oxygen to the muscles, and improve neuromuscular co-ordination. This will enable you to maximise the effects of training through the ‘build’ phase of your program; I find it gets me running quicker within each heart rate zone and gets me tuned to my training.

“No no… I was not very talented. My basic speed was low. Only with willpower was I able to reach this world-best standard in long-distance running” – Emil Zatopek, the father of interval training.

There are four variables for intervals: 1/ itensity (speed) of workout; 2/ duration of work (fast burst); 3/ duration of recovery interval; 4/ number of repetitions. Treat the intensity of your workout with caution; set a pace that is just above your threshold pace and do not be tempted to run flat out. Threshold pace is typically defined as your 10k pace (see Lore of Running for more depth on training pacing). Note that during the peaking phase this is gradually increased to 5k and 1-mile pace to sharpen.

Try this great workout: 300m @ 10k pace / 100m or 2 minutes recovery. If you are new to intervals, start with 10 repetitions; more experienced runners can perform 15-20 repeats. Use the pace calculator to establish your target pace. If you’re using a heart rate monitor, your HR should recover to the 120s during the interval. Your local track is the ideal place for interval sessions; failing that, mark out the distance on a flat, smooth, quiet section of pavement or go to a nearby park.

I ran 15 reps at 1.06 per 300m – based on a 38 minute 10k time – with my HR around 165 during bursts. Note this is slightly quicker than my PB as I’m looking to carefully increase my pace. Running too quickly will not lead to noticable training benefits over 10k+ distances.

Cycle faster

Bike intervals

So far, sportives have been fun. Getting used to group riding, raising my average pace, increasing the distances covered at this pace. But something has been missing. When the bunch hits a short incline the strong riders rise from the saddle, step on the pedals and power away. When somebody darts out from the pack, the strong riders leap onto their wheel with a burst of speed. This is what’s missing from my cycling: I need more power.

Today I went to Regents Park to do some intervals. My dual aim is to: 1/ increase my overall sustainable pace (long steady rides are fine for base building, but shorter faster rides will increase my sustainable riding speed); and 2/ increase my pedal power.

On the Outer Circle I used the straight from the south east corner up to the north east corner (exit to Parkway) for my flat out bursts. This is a slight incline, levelling out two thirds of the way up, and came recommended by Al. The remainder of the loop was the recovery time.

A scientific approach would match the level of intensity with my precise anaerobic threshold. But – in the absence of this data – I aimed to simply ride as fast as I could evenly sustain during the near maximal exertion. This was generally 24-25mph – hitting 27mph at one point – and getting my heart rate up to 175bpm. The rest of the loop is flat so – whilst recovering – it’s easy to spin a fast yet easy cadence and maintain 20mph, heart rate dropping to approx 130bpm. For me this simulates sportive pace bunch riding and suited my objectives.

I did 6 repetitions, then headed home via Primrose Hill, Hampstead, and Highgate. To add some spice to the session I restricted myself to the large chain ring and powered up the short London hills (an alternative would be hill reps). Adding interval training will improve both my sportive performances and my triathlon time-trial riding.