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Why and How to Incorporate Interval Training

Interval training makes you faster, but how?

When your muscles work hard, they produce lactic acid, and if you’re always running at a comfortable, steady pace, your body has enough time to flush it away. As you work harder, the lactic acid starts to build up, which causes your muscles to burn (and your desire to stop grow strong). That’s your lactate threshold, and interval training is all about encouraging your body to do everything it can to offset this point and cope mentally. Which it does, so you can run faster, for longer. Your body responds to interval training by growing extra capillaries that transport more oxygen to muscles, strengthening your heart to circulate it around, and all while developing the capability to filter more lactic acid.

The periods of effort need to be tough enough to push you just above your lactic threshold and your periods of rest are equally important, if not more so. You’re training your body to cope with the lactic build up, and by coping with it, you are able to run faster, longer. So the speed isn’t as important as pushing yourself just past your limit, then allowing time to recover before doing it again.

When you decided to be a runner, it’s likely you combined walking and running until you were able to tie a few miles together without walking. Interval training should be approached the same way. Bones, tendons, muscles, and the brain need time to adapt to the stresses of interval training, so take it slow if you’re new to it.

How to Incorporate Interval Training 

Choosing session lengths depends on your goal race distance, your fitness level and your own preferences. Common sessions include 10 x 400m (60-second recoveries) up to three or four mile-long efforts (with three-minute recoveries). It can take some time to get the lengths right, so be patient with yourself.

Don’t start out like a bat out of hell, your first and last interval should be run at the same pace. Remember, it’s the recovery that you’re trying to improve, which will in turn improve your speed and overall race times.

If you’re sore the next day, you probably overdid it. You want to work towards not overdoing it next time. Remember to pace yourself, intervals train you to run your goal pace to finish under your desired time, whether it’s a 7-minute- or 10-minute-mile pace

Types of Intervals

Standard intervals are when you run for a definitive distance, followed by a recovery jog of a specific distance, and repeat.

Pyramid intervals (ladders) are sessions that include a variation of the standard interval session, where you would run in ascending or descending intervals. An example of a typical session would be running 800m, 600m, 400m and 200m, each followed by a recovery jog.

Fartlek (yes, it’s funny sounding but it means ‘speed play’) intervals are unstructured and involve a variance of intervals (hence having ‘play’ in the name). You can explore different types of terrain and add in power moves - like bounding, stride length and changing directions).

Hill intervals involve, you guessed it, hills! Basically you run uphill for a set period of time, and jog down, and repeat. These sessions are excellent cardio workouts and also help with strengthening the legs.

Example Interval Workouts


  • -400m warm up jog
  • -Start set one with 2x200m sprints and 2x400m sprints with full recovery inbetween intervals
  • -Repeat sets twice 5 minutes recovery time in between each set


  • -400m warm up jog
  • -Run four quick 50m sprints
  • -Then start your sets of 3x400m and 800m intervals with 2 minutes recovery time
  • -Repeat sets twice with 3 minutes recovery time


  • -600m warm up jog
  • -Run four quick 50m sprints
  • -Start your set of 4x400m and 1200m intervals with 3 minute recovery periods
  • -For the second set take 4-minute recovery times.

Again, start slow. Most runners set aside 2-3 days a week for interval training, depending on your current level and your goal.

Now get going. But first, check out upcoming Runwell events and sign up. You need to practice those intervals, right?

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