I have "agreed" to run a half marathon at the latter part of this year and am really apprehensive about doing so. I started running last May and completed a 10k and 5k race towards the end of the year. The snow hasn't helped lately but I usually run two evenings (approx 5k each run) and once on the weekend (up to 10k). As I am at the beginng of the year I wonder if its worth amending my running measure from metric to imperial so that I can start to focus on miles run rather than kilometres. This will possibly mess with my head but it might help me physiologically towards the half marathon. Does anyone think this is a good idea? Can I successfully train for the half marathon by running three times a week? The race is it until October so I have plenty of time.