After Mark Armstrong had completed his Edinburgh Marathon he said to me that he was pleased to have finished the run, but was still very disappointed with his time.

He said that he felt like he had let people down as he knew he could go quicker and wanted to run another one in September.

My reply was that you most definitely have not let anyone down and, irrespective of how you currently feel, just give it a couple of weeks so as to let everything settle down.

Let the body fully recover and let your emotions subside before making a decision.

After such a test of endurance, it is always a case of mixed emotions where those who had a good run are on a high and the elation disguises some of the aches and pains.

For those who feel they should have done better they are still fired up due to disappointment and wanting to get out there and prove to themselves and others that they can run much quicker.

MORE: Master the mind before running a marathonThe month after completing a marathon is in some respects just as important as the months leading up to it. Whether you feel you produced a good performance or can do better, the truth is that your body needs a well-earned period of recuperation.

The amount of times I have seen people go down with heavy colds or injuries just weeks after the event and all due to not allowing for an adequate period of recovery.

Once you are fully recovered not only will you feel so much better, but you can then make clearer decisions and if the thoughts are still towards running another marathon so soon after completing the last one, then at least your legs, body and mind will be recharged and ready to go again.

In Mark's case he's looking for a much quicker time and having now run the distance he can fully get his head around what running 26.2 miles is all about and have the confidence to set out at a realistic pace to cross the finish line in a time which matches his true potential.

One thing which is for sure is that it doesn't matter how many people give you advice prior to your first marathon, it is actually running one and experiencing everything which goes with running such a long distance which will help prepare you physically and mentally for future races.

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