› Run Speed

Improve Your Triathlon Run

Why Include Speed Training?

With the triathlon run accounting for the second largest section of a race (~ 25% of total time), improvements to running speed will inevitably result in improvements in triathlon speed…..or will they?

We have seen some athletes improve their running speed over 10-k but then make fairly insignificant improvements in their triathlon running speed.

Why is that?

The simple reason is that when you start the 10-K in an Olympic distance triathlon you are probably quite fatigued already. All that running speed you spent months working on cannot be accessed because you are too tired and using an entirely different energy system and your muscles are in an entirely different condition to what you were training for.

Therefore speed training for triathlon is different to speed training for running alone.

If you have any questions about your triathlon training then please ask us.

REMEMBER: We use the term SPEED training to describe any type of training that trains you to go faster. ENDURANCE training describes sessions that help you to continue for longer at the same pace.

For the majority of triathletes there are two crucial areas to work on to improve speed for triathlon running.

  1. Lactate Threshold 1
  2. Lactate Threshold 2

If you have read the pages on physiology and specifically the descriptions of thresholds you will know that:

1. LT1 is the point where carbohydrates are starting to be used a bit more than at rest. Assuming your endurance is good you have fuel to run at this pace for quite a while (1 – 3-hrs).

2. LT2 is the point at which you are relying almost exclusively on carbohydrates and as a result there is a raised but manageable level of acidosis in the muscles. Again assuming endurance is good you have energy supplies to last about 80 – 90 minutes at this intensity.

The extreme duration of both examples would require you to be very well ENDURANCE trained!

The speed at which these two points occur will dictate your potential to run off the bike. It then becomes your ENDURANCE at this speed that will dictate how long you can sustain this speed.

Differing race distances or durations will dictate which of these two points is more relevant to performance.

The table below shows the relative importance of each threshold to the various distances for an average competitor.

Distance Lactate Threshold 1 Lactate Threshold 2
Sprint Medium High
Olympic Medium Medium
Half Ironman, 70.3 High Medium/Low
Ironman Very High Low

So improving triathlon running speed, or more importantly improving triathlon run time, is all about raising the speed at which these points occur.

You then need to improve the ENDURANCE at those speeds. Remember you’re not just training for a running race, you’re training for a triathlon!

Improving your speed and then your endurance may sound a little strange as many programmes will build endurance first before developing speed. But whilst you might have increased the speed at which your thresholds lie, you need to then improve your endurance at these speeds.

Do I Work on Speed Or Endurance?

Below are two examples that illustrate how to determine which type of training you need to focus on:

Example 1 - Olympic distance athlete takes 2h 25 to complete the race.

  • 25-min for the swim
  • 75-min for the bike
  • 40-min for the run
  • (plus a little from the transitions)

You cannot sustain this duration (2 hours 25) at LT2, so part of the race will be at a lower intensity. In this example the athlete’s LT2 must be over 15km/hr (40 minutes for 10-k) to enable them to perform this time.

To perform the run section faster there are two main options:

1. LT2 is significantly higher than 15-km/hr:

They do not have good endurance and therefore are unable to sustain that intensity for long. If this is the case, improving running speed will have no effect on the triathlon run speed, as it is not the limiting factor. ENDURANCE is the limiter – being able to run at LT2 for longer.

To improve their triathlon run they need to spend more time on Intermediate ENDURANCE training.

2. LT2 is close to 15-km/h:

This athlete will not be able to run better than about 40 minutes for the 10-k until they improve the speed at LT2. Therefore improving SPEED at LT2 will be a significant part of making improvements to triathlon running speed.

Example 2 - Ironman athlete takes 11h 15 min to complete the race.

  • 1h 30 min for the swim
  • 5h 45 min for the bike
  • 4h for the run
  • (plus a little from the transitions)

This is obviously an event that is dominated by aerobic (fat burning) metabolism, and therefore LT2 is almost irrelevant. LT1 however is a key running speed for this athlete, as it marks the boundary between almost exclusive fat burning and the start of increased reliance on carbohydrates.

This athlete has set themselves the target of running sub 3h 40min at the end of the race.

The 4 hr marathon is an average speed of 10.5 km/h which means that the athlete’s LT1 has to be higher than this point. A 3h 40 min marathon means sustaining an average speed of 11.5 km/h, and for this to be possible LT 1 has to be higher than this.

Similar to example 1 there are a couple of key areas to look at:

1. If LT1 is already significantly above 11.5 km/h then the athlete is underperforming in the triathlon run, and needs to improve ENDURANCE at this intensity.

2. If however LT1 is not significantly above 11.5 km/h then running SPEED is the limitation and the speed at LT1 needs to be developed. Then suitable endurance at this point will need to be built to enable the 3 h 40 min run.

To find out how to assess where your LT1 and LT2 are, see our fitness testing pages.

Are There Any Other Factors To Consider?

There is a third variable that we would include when talking about improving running speed.

This is VO2max.

It doesn’t directly influence triathlon running speed as most triathlons are usually completed at submaximal intensities, but it does influence the trainability of LT1 and LT2.

VO2max sets the upper limit for your performance. There comes a time in anyone’s training when they are so well trained that the limiting factor is neither threshold measure, as they able to sustain these intensities at very high percentages of the ‘ceiling’.

To move forward this ceiling has to be lifted to allow you to continue to improve.

What Do Sessions To Improve Your Triathlon Run Speed Look Like?

For a comprehensive description of ‘speed training’ sessions to include in your triathlon training program to get your triathlon run faster have a look at our How To Increase Running Speed page.

Where Does Training To Improve Speed Fit In My Triathlon Training Program?

To understand how to put your program together as well as when and why to include sessions at particular time, follow our guide to putting your triathlon training program together.

It explains more about how to use the SPEED and ENDURANCE sessions and helps you to decide when to use them to improve your triathlon running speed.

Summary Of Why To Include Speed Training:

  • Training to improve speed consists of working on shifting LT1 and LT2 to a higher speed.
  • Training to improve endurance allows you to sustain the speed at these points for longer.
  • You might need to lift your ceiling (VO2max) to allow you to improve the speed at which LT1 and LT2 occur.

Got a question about your triathlon training?
Then please ask us!

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