Tall claim?



Will show you the steps below

It works?

Yes…From way earlier and was published in Runner’s World magazine on 1977.

So, what is it?

Take your running to the next level 😮

This is all of our dreams.

We either want to run a sub-2-hour marathon or may want to participate in the next 5K

But how to know where to focus to get the maximum result.

This is how…

Use this formula developed by Peter Riegel (More about him, here)

His formula was published in 1977 issue of ‘Runner’s World’

Now the obvious question is, 

Who is Peter Riegel and why you should listen to him? 😕

Peter Riegel (1935-2018) was an American research engineer.

He developed a mathematical formula for predicting race times for runners.

His entire formula was based on a certain performance of an individual at another distance.

This formula is widely adopted for its simplicity and accuracy of prediction…

Ok Ok…Will you give me the formula already? 🙄

Ok…guess you don’t like history…

Anyways, here is the formula…



T1 is the time achieved for D1.

T2 is the time predicted for D2.

D1 is the distance over which the initial time is achieved.

D2 is the distance for which the time is to be predicted.

^1.06 means the percent increase in time for every doubling of the distance

Riegel expanded on his thesis in a 1981 article for American Scientist.

He stated that the formula t=axb concerns activities in the “endurance range”, namely lasting between 3.5 and 230 minutes.



x = (D2÷D1)

b= 1.06

The analysis deals with exercises like running, swimming and walking.

Example time… 😎

I could not understand the head or tail of it until I crunched in some numbers.

I am dumb that way. Without example, I cannot understand 😜

So, here is what I did,

Let’s say, I’m currently running 400 meters in 60 secs

I want to run 800 m

Then how much time should I take?

Using the formula,


It will be,

T2=60×(800÷400)^1.06 = 126 secs (approx.)

However, when Reigel came up with this formula, he included elite athletes’ performance into consideration.

For a common person like me, a 6% increase in time is not only too ambitious but also not at all realistic.

✅ What is a realistic percentage?

With my initial testing, it seems like somewhere between 18 to 21% seems to be realistic.

So, after fine-tuning the formula, it should be something like this.


Back to the previous example

If I want to run same 800 m in a non-elite athlete way, 😱

then it will be

T2=60×(800÷400)^1.21 = 139 secs (approx.)

Enough Theory… Tell me how to Use It? 😏

Well this is the fun part.

Here is my step by step approach…

⚠️ WARNING: ⚠️ You have to get sweaty and dirty… 

Step 1: Determine your baseline

Check how much time you take to run your 400 m or any other distance of your choice.

But don’t go beyond 1 mile.

So, for me running 400 m takes around 52 secs.

Let’s take it as the baseline and we will assume that our running time will increase by 21%

Step 2: Determine how much distance you want to run

The next step will be to determine how much you want to run

This is completely dependent on you

You can choose any distance.

Let’s choose 5 mile or 8047 m

Step 3: Crunch in your numbers

Now simply apply the formula.

T1= 52 secs

D1= 400 m

D2 = 8047 m


T2 = 52×(8047÷400)^1.21 = 1965 secs or 33 min (approx)

So, now you know that if you can hit this number or a little less for a 5 mile, you are on track. 💪

😇 Second Way To Use The Formula 😇

Let’s suppose you want to improve your time.

Say from 21% your want to go to 18%

So, initially we got the time for 21% as 33 min

Now let’s calculate for 18%

T2 = 52×(8047÷400)^1.18 = 1796 secs or 30 min (approx)

With that clear number, you can tailor your schedule accordingly to improve your time

Is it accurate? 🤔

This formula is widely adopted by athletes.

But I did my own little experiment 😁

I followed the exact steps given in Way #1

Firstly, I determined my base time.

That is when I came to know that I take 52 secs to run 400 m.

Next I determined the distance I want to run.

I can comfortably run 5 miles now.

So, last Saturday, I went for a 5 mile run.

My expectation was that I should be able to run it within 33 min which is a 21% increase of time

My result was close. I took around 35 min (😑😑😑)

But anyways, I know that this formula works at least approximately.

So, my next target is to fit my running time within 33 min.

Once, done…I’ll shoot for 18% increase

Who knows, by end of next year, I may be able to run at a 6% increase.

Ha ha Madhu, Dream on!!!!

How to improve your running performance? Here is the only thing that you need to do, to take your running to the next level. Find out how easily you can run at your best.

How to improve your running performance? Here is the only thing that you need to do, to take your running to the next level. Find out how easily you can run at your best.

Madhusree Basu

Madhusree Basu

Author, Admin

Blogger and a fitness enthusiast. She loves running and Yoga and everything in between. She started running to manage her weight and to eat to her heart’s content. A true foodie at heart she shares whatever knowledge she has gained throughout the years about weight management and fitness.