Long and slow, or short and sharp? February 05 2015, 0 Comments

Up until recently, the most common refrain that I heard about distance running was that you should do some long, slow running for stamina, and some faster work to build speed.  The extension of this was based on heart rate, with 80% of training time at 60-70% of the maximum heart rate (often called the 'fat burn' rate), and the remaining at 80% or more.

An extension of this, and a theme that I am hearing more and more, is that short, sharp bursts of activity and rest are actually much better for getting fit.  Recommended times vary, but distinct improvements in fitness have been recorded with less than 5 minutes a day.  The interval training involves 20 seconds or so at absolute top speed, followed by a rest period of 10 to 40 seconds.  I have tried this myself at a track near here, and with a heart monitor, and here is the result.

I did about a 6k warm-up, so the relevant bit for the intervals was the spiky bit at the end.  I did five, about 100 metres, followed by 300 slow, and you will see there are five peaks towards the end with a gradually ascending maximum.  Two observations on this.  Firstly, by the end of the last interval I was whooping for air, so my lungs definitely got a clearout.  Secondly, sprinting like this, you use the full travel of your stride, bringing the knees right up at front, and extending back hard for the thrust.  This addresses a concern that I have about always running long and slow, in that the muscles are not used through the full length of their travel and I don't believe this is best for them.

Later that week, I ran with my usual group, and I have to say found it easier, and clocked a better speed than before.  So the interval training stays from now on.