I've started back running and I'm on a 30 week training programme for the Dublin Marathon at the end of October. I'm a 5ft 10 male, weighing 16.5 stone so I'm about 4-5 stone overweight.
My pace at the moment is very slow. I think I've broken 40 minutes for a 5k twice, but only just dipped into the 39 minute range and even then, that was over a year ago. Now, 5k usually takes me about 42 minutes. I used the MacMillan running calculator and it says a marathon will take me 6hrs 51 minutes based on my 5k time! That is far far too long. If I run consistently for the next 7 months and drop some weight, how much faster am I likely to get? This is without doing any specific speed work.