Robinson wants to set a new personal best in the London Marathon (Getty)

The 33-year-old Commonwealth bronze medallist has the qualifying time for Beijing and was originally looking to run shorter races in the build-up.

"I thought the training that I would be doing in eight months was a long time to focus on one race," Robinson told BBC Radio Gloucestershire.

Robinson came ninth in the 2007 event, with a time of two hours 14 minutes.

During his career Robinson has concentrated more on being well placed in championships, rather than his times in races, but now he wants to race the full distance against the clock.

"I haven't really worried about the watch, so it would be nice to run a fast city marathon.

"Championships are not really about times, they're about positions and they're often on pretty tough courses in the middle of summer."

"My personal best is two hours 13 minutes. I'd like to get that down to as close to 2:10 or 2:11 as I can."