Pacing a marathon

On Sunday I'll be running the London marathon for the first time. I was lucky enough to get my running club's only place (thanks Fulham Running Club!) and as it's in my 'home' town (unless there's a Sunningdale marathon I don't know about) I'm excited about taking part.

As they say in the US, this ain't my first rodeo, though. It will be my fourth road marathon so I know a bit about what to expect. Part of this is knowing that you need a plan, however vague, if you want to hit any target beyond simply finishing. And although this isn't my B race for the year, never mind my A race, I do want to give it a good crack.As I'm nowhere near 'good for age' (sub-3.15!), I may never get the chance again.

Before I go any further, here's where I get my pre-race excuses in. Since last May I knew I'd be doing the North Downs Way 50 mile race this May, so when I got into London which falls three weeks before, I felt I had to make a choice. Train for one of them and hope the other worked out. So, most of my training has been slow and hilly which should stand me in good stead for Box Hill and environs but possibly isn't so ideal for a PB attempt around the nation's capital city.

But as the London marathon has got nearer, I've become more excited about it and rather than simply get round the course, I've been planning my race strategy and pacing. Conventional wisdom suggests an even paced race is best, or maybe even a slight negative split (second half faster than the first). Realistically, very few achieve this as my past races prove (see below). Hitting that sweet spot is tough though. Set off too fast and you die in the second half. Set off too slow and you might get a negative split but did you really push yourself hard enough?

2013 - Belfast

My first marathon and with a target of 3:45, I hit halfway almost bang on schedule but simply didn't have the fitness to maintain it. An 8-mile uphill section in that first half probably didn't help but in the end my lack of endurance did for me. With about 9 miles still to go. Moral of the story: first marathons are hard!

0-13.1 - 1h53m
13.1-26.2 - 2h03m
Time: 3h56m


2014 - Edinburgh
This came six weeks after the South Downs Way 50. My training in between had felt lethargic (perhaps unsurprisingly) and although I hoped for a PB I wasn't sure how fast I could go. Taking a cautious approach, I got to halfway feeling comfortable and just felt better and better as the race went on. Mile 26 was my fastest and I didn't want it to end. Moral of the story: ultras make you faster.

13.1 - 1h50m
13.1-26.2 - 1h48m
: 3h38m

Taking it easy at Edinburgh in 2014

Taking it easy at Edinburgh in 2014


2015 - Kingston
Despite a distinctly sub-optimal training block (albeit including a great two weeks eating my way around Europe), I decided I should go for sub-3:30. I hit halfway on target but even by then knew it was an unsustainable pace. The last eight miles were agony. Another PB but nothing like the elation of Edinburgh. Moral of the story: do the training.
0-13.1 - 1h44m
13.1-26.2 - 1h50m
Time: 3h34m

And now for London.

My longest run in training at anything above an easy trot was 18 miles and even that wasn't at target marathon pace. Maybe it doesn't matter. Maybe the crowds will pull me along. Maybe hiking up hills in Surrey will finally pay off. 

So my aim is to run even splits by reaching halfway feeling okay and sneak a PB. It probably won't work but I'll give it a go. What's the worst that could happen?