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Running – How to know if your training is balanced and what to train

Wondering what components of fitness to look at and how to address them? Let's start with three big ones for now.

1. Raw Endurance

Is the ability to basically run far at a relatively fast pace (relative to your ability).

2. Lactate Threshold

Is the ability to run and sustain a fast pace for around 60mins

3. Speed

Is the ability to run fast over short distances.

Below is a table to give you an idea of some of the concepts around each major distance.

Table showing fitness components and their importance in each phase

Below I will explain some of the criteria to consider when deciding if that particular fitness component is important to work on through different ways to measure that component.

Raw Endurance

At The Threshold, we use Training Peaks to measure track and monitor our athletes' workouts. Various metrics exist within the software that allow a runner to really see some objective number driven change. One such metric is called Aerobic Decoupling. What this particular measurement means is that the first part of the workout is compared with the second part and a % is given in terms of how much speed/power and heart stayed coupled with each other. Well trained endurance will stay under 5% on a steady long workout as their speed and heart rate stay coupled.

Do this: go out on your long run and keep a steady heart rate or speed (speed is easier on a flat course). Alternatively, with Stryd power meter, you can keep a consistent power and analyze how average heart rate as two couples. The software will do this for you! See pictures below:

Picture 1: Notice Pw:Hr was under 5%. This means power and heart rate did not decouple. In other words, heart rate didn’t go higher while power stayed the same or dropped.

Picture 2: Notice Pw:Hr over 5% which indicates decoupling of power and heart rate. In other words, heart rate began to get higher, while power stayed the same or lessened.

Lactate Threshold

Lactate profile of an athlete is a graph that shows running speed against blood lactate concentration (see picture 3 below). The graph moves from the left and as speed increases, so does the concentration of blood lactate, with a very shallow upward slope at first, then becoming much steeper as intensity reaches maximal levels. The sudden steeper portion on the graph represents the lactate threshold value and often occurs at a level of around 4mmol/l. There are obviously differences amongst individuals at which this point occurs exactly. However, onset of blood lactate (OBLA) is generally considered around the 4mmol/l value.

Picture 3: The blood lactate curve of a runner with power (remember speed can also be plotted against lactate profile, the point is to see where that lactate curve changes and at what speed/power).

The goal for a runner seeking to improve performance would want to see the sharp rise in lactate accumulation in the blood shift to the left so that speed increases for all lactate measures compared to previous measurements.

*A note on running power. While an increased power output for any given speed may be seen as an improvement in performance. Careful consideration must be given to speed at those power outputs. If speed increases for the same power output, clear improvements in running efficiency has occurred. Don’t get sucked into more power is more in running. Discretion is advised! Or get a coach to help!


This is considered your maximum speed you can attain in a full sprint.

How to use this information

One of the quickest reference sources is to use Pace Zone Index (PZI). Essentially you would see what pace you achieved on a long run, threshold run, VO2max intervals and finally your top speed on a sprint. Then go to the tables below to see where all your information lines up.

For example (please note tables below is in min:sec per mile. I use min/km)

  • Ryan Runner has a recent 5km race result of 20 min 01 secs.

  • This puts him at a PZI of 28

  • His 90min long run pace averages- 5:05 min/km

  • His Threshold 2x10 min average pace for the 10min segments- 4.10 min/km

  • His VO2 max 4x3min average pace for 3min segments – 3.48 min/km

  • His maximum speed he achieves on a full sprint is 19km/h or 3.09 min/km

According to the PZI, Ryan Runners threshold speed needs some attention as it is below the expected zone 6 speed for his 5km race pace. Also, aerobic decoupling can be applied to his long (keep it less than 5%). He can get a lactate test done and see where lactate accumulation (OBLA..see above) occurs and work on moving that. From his above numbers, it would seem moving the curve to the right is a good training approach. His test would reveal the precise details.

(Tables taken from

Last thoughts

Many different types of analysis of performance exist and go beyond the scope of this article. The above PZI is one such method and a very simple one (the best ones are!). At The Threshold, I further use WKO5 to analyze my athlete's running performance if they are using running power. In future articles I will discuss VVO2 max, resistance to fatigue and running economy to add to the above ideas.

Train Hard and Prosper


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