For an event where endurance is such a prime requisite, it may seem odd to mention speed as another significant factor, but a glance at the pedigree of Germany's Irina Mikitenko, aiming for a hat-trick of wins in Sunday's Virgin London Marathon, and New Zealand's Kim Smith tells a different story.

Mikitenko honed her competitive edge to considerable success on the track, finishing fifth and seventh at 5,000m in three successive Olympics, beginning with Atlanta in 1996. That paved the way for a marathon debut in Berlin in 2007, joining the elite club of nine women who have broken 2:20 for the event and the start of her unbeaten run in London the following year.

This is a path that Kim Smith would dearly love to follow. Her marathon debut in New York in 2008 was blighted by a heavy cold but the New Zealand record holder at 5 and 10,000m takes inspiration from the track career of the reigning Virgin London Marathon.

"I'd like to think my track speed could make a difference in the marathon. I look at Irina, she's come from a track background and she's done really well. It's the same with the Russian Liliya Shobukhova who won Chicago last year and is running here, she's very fast on the track. I think it will help for sure."

These days Irina Mikitenko prefers to concentrate on road racing and to ration her appearances to when she feels ready to give her absolute best. A competitive break of more than six months since finishing runner-up in the Chicago Marathon last October leaves her unruffled.

"It doesn't make me feel anxious at all. I did the same between London and Chicago last year. My form is good. The winter was hard for a lot of us European runners because of the snow. We had to improvise a lot but I'm in good shape now."

Kim Smith, having now run three half marathons since dropping out of New York two years ago, and setting a New Zealand of 67:55 in New Orleans on February 28, admits that the waiting game in race week is one of the marathon's challenges.

"I definitely feel worse than normal but my coach tells me it's my body getting ready for the big event as I cut back on training. I talked with Deena Kastor [the US marathon record holder and 2006 London champion, who will also be running on Sunday] and she encouraged me, saying everyone feels like this."

Although she has speed at the shorter distances, the New Zealander is wary of following too fast an early pace.

"I think I would feel a little afraid of going with a sub-2:20 pace. My coach wants me to, but I'd rather be running at 2:25 tempo and see how the race goes. As for my goals, I'd love to finish in the top three but it's such an amazing field."

Mikitenko did return to the track herself during the snowbound European winter, doing at least some long runs on an indoor track in Frankfurt. As the women's champion for the last two years she remains confident but not complacent.

"The big advantage now is that I have experience of London but this is a new race - it's different every year and there are lots of women this year who want to win."