Using a calculator to work backwards !! - Marathon Running ...

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Using a calculator to work backwards !!


I have a running equivalence calculator which is usually used by say putting in your current 5K pace and it tells you what your potential 10K and HM paces are provided you do the training :) I have done a number of 10K's and HMs and found it to be quite accurate. However having done 3 HMs and at those events thought I could not even contemplate going around the course again!! :) , I can see that the marathon distance will be for me like sailing into the unknown seas in old days. :) Using the aforementioned calculator, it is telling me that I have the potential for a 5 hour 20 mins for the marathon. BUT I am ignoring that dream. I will be content to get across the finish line within the official cutoff time of 6 hours 20 minutes - so putting that time into the calculator and working backwards it then tells me what times I "should" be able to run the shorter distances. The time it tells me for 5K is quite easy for me and this week I am running a 10 K as part of the training and I am supposed to be able to do it in 1hour 18 mins. I have done it in the past in 1 hour 6 mins but I am way off that level of fitness right now but I think I should be able to do it in the required 1hour 18. I am intending to do a HM in about 5 months time and it is telling me I need to do it in 30 minutes slower than my best time ( but once again I am way off my best times right now and unsure that I could ever get back there) - anyways it gives me some mindgames to play with myself :)

10 Replies
TbaeMetric Marathon

Interesting Bazza.

I am sure with your determination and experience you will recover your previous levels of fitness.

I am very much a novice and really just getting interested in local marathons.

I am in the process of checking out trail marathons and the severity of the terrain, must say your cut off times are not generous when comparing ball park figures for events around here.Not easy to compare I guess.

Your still achieving good things Bazza,very good , and I am I sure at 6:20 I could not cross the line in time for any given terrain.

Enjoying the challenge and build up though.

Who knows what magic appears one day.

Atb with your honest endeavours.


Bazza1234Marathon in reply to Tbae

TBAE - this event is our local version of the London Marathon :) Here is a bit of inspiration for you :) and some longer entertainment

TbaeMetric Marathon in reply to Bazza1234

Yes Bazza,

that is truly inspirational and thank you for your kindness.

I will take the time to watch the 2nd one through this evening.

Garden calling.🙈

Take good care of you Bazza, you are doing great and keep inspiring the forum.


Bazza1234Marathon in reply to Tbae

I posted the wrong link - this one , last years marathon had the most incredible finish I have ever seen We were close to the finish line and could see that the Kenyan was "cruising " well ahead and the Japanese was exhausted - but the Japanese had a hidden jet engine which nobody knew about and won the race . Incredible

TbaeMetric Marathon in reply to Bazza1234

Just Brillant Bazza.

Thanks for that.👏👏👍

The commentary is full

of general running detail also.

Unlike ours it is more about people’s stories.

Not judging, just an observation.

My son in law’s parents are Aussies, and I have heard them comment about the lack of detail in our weather reports compared to their own,this comparison makes me appreciate their point perhaps.

Thanks Bazza and good luck with your programme.I will watch with interest.


ancientrunnerHalf Marathon in reply to Bazza1234

Goodness Bazza, where did he get that spurt from!!! Sheer willpower.

I quite like playing with those calculators but often think they just multiply or divide the time you put in and don't account for tiredness creeping in. Would also be happy just to get over the finish line

Bazza1234Marathon in reply to ancientrunner

That Japanese runner - when the two frontrunners passed our position about 500 metres from the finish line , he was BEATEN!! If anybody had bet me $500 that the Japanese man would win , I would gladly have taken their money!!! Where he pulled that finish from I have no idea - he was 30 metres behind at the start of the final 150 metre finish lane and finished 20 metres ahead!!!


Ahh. I do like number based mind games :)

Do you have a link for the calculator by any chance?


Thanks for that reference Bazza. I found this online variant just now. Not sure if it works the same way as your model, but it helped me determine my HM time based on my pace today:

Bazza1234Marathon in reply to Decker

Yes - there are a number of them . I usually use this one from the American trainer Jack Daniels - but he doesn't even use the concept of "recovery runs".

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