After months of distance training, I'm focusing on speed.
It is officially one month until I take on the London Marathon for Amnesty International and after a gait analysis revealed that my previous footwear had me wobbling like a newborn giraffe, I invested in new kit and am already feeling the benefits.
This week, however, I came across a new hurdle in training - boredom.
After a day at work (or an evening of over-indulgence) there can be times where the thought of heading back out and running the same route over the same distances can wear resolve thin.
The idea of concentrating on speed training hadn't really occurred to me until I had a conversation with a friend who completed his second (and last) marathon last year. It turned out that his speed training came in handy in the final third when he was briefly overtaken by Uncle Bulgaria fom the Wombles.
I had been concentrating on making the distance. It hadn't even occurred to me that I would find myself in a sprint finish against a children's television character. So speed training it is.
For this week's training I was able to try out a pair of K-Swiss Blade-Max Stable shoes. While the name might be eye-catching enough, the shoes themselves certainly don't shrink from the limelight.
Decked out in luminous red and yellow, they are so flamboyant that I felt like I should have been running wearing a feather boa. But comfort comes before style and slipping my feet into these immediately made me forget any design concerns. They were spectacularly comfortable.
Upon setting off towards Kingston I was immediately aware of the size of the shoes, which seemed designed to look like bulky basketball boots rather than sleek speed machines.
However, one look at the sole reveals that the shoes' size is due to an elaborate system of rubber blade shapes, which act as suspension while flicking away sand and grit for the serious off-road explorer.
This could seem like overkill for my jaunts through suburbia, but anyone who has tried to run along the Thames Path on a morning will testify that the amount of broken glass, passed-out students and kebab meat will test any footwear.
Sprint training gave me the refreshing alternative of stopping because I was on the verge of keeling over, which was at least a change from the usual slow war of attrition that sees me grind to a halt over 18 miles.
Hopefully, a few more weeks of speed, coupled with weekly distance training, should see me hit my sub-four-hour target. At the very least I should beat anyone dressed as Bungle.
Nick is fundraising for Amnesty International and hopes to raise £1,800. To sponsor him visit his fundraising page.