We may have been friends for more than half our lives, we may have been training buddies, and we may have run Brighton Marathon 2012 together – but for the next 10 days, SportyGirl and I are rivals. Not since Seb Coe and Steve Ovett battled each other in the 80s has running known such an epic rivalry.

Both of us are running 10K races on the same day, SportyGirl is doing the Bushy 10K a local race in our home town Peterborough, while I will be running round the streets of London with 40,000 other runners in the British 10K. Last night a bet was made and a wager agreed: whoever takes the most seconds off their current 10K PB is the victor – the loser buys dinner.

My current 10K time stands at 51:06 and is from 18 months ago, SportyGirl’s is 54:18 from two years ago – it’s fair to say neither of us are big fans of the 10K distance. Watch this space for pictures of me buying her a burger and chips in 10 day’s time.