Well, you could have a 10 second breather, but you would have to include that into your calculation of the overall finish time
! However, that is a good holding of pace over the 10km, considering that actually that pace isn't far off your 5km max pace, so that's a great session Mike, well done!
Mike, 5k and hm require quite different training. Whilst you could do a half as a long run, you probably wouldn't feel like you'd done yourself justice if you tried to race it off specific 5km training. Having said that, if you were able to get a build up of a couple of months, maybe not for the GNR as that's a bit close to the end of the track season, but perhaps something in mid to late October or early November, you could afford a couple of months of base mileage work as winter training, which would allow you to train specifically. It would have to be factored in to an overall training plan by someone who knew what they were doing coaching-wise as part of a long-term strategy, but a couple of months of slower running at a higher mileage, followed by some hardcore speedwork can pay dividends in the long term by improving the general fitness base on to which to then build the faster training, but only if the athlete and coach are patient and have a long term view, as in the short term the athlete go slower over the shorter distances.
I'm personally planning a half marathon followed by a short xc/indoor season in in the first part of this winter - I'm not planning to run well in the shorter races, but these are part of the overall plan leading into next summer's target races. I don't know if it's going to work yet though, this is my first time doing this! I'll let you know in May....
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