Respiratory physiotherapist Anna Boniface will race in the Toronto marathon on 22 October representing England.
She is one of two women in the six-strong England team.
Ms Boniface smashed her personal best at the London Marathon in April by seven minutes to run two hours 37 minutes.
She was the first ‘non-elite’ woman runner to finish the London Marathon.
Speaking to Frontline ahead of Sunday’s event in Canada, she said: ‘It is very exciting having my international debut.
'I'm now in Toronto acclimatising and feeling rather jet lagged. The next few days will be just turning my legs over.
‘I've had a good three weeks or so of training and won the Bournemouth half marathon in a new course record two weeks ago and did my local cross country league on Saturday.
‘The Toronto race aims will very much be focused on gaining international experience rather than running fast times.’
Ms Boniface works in the community rehab team at St Mary’s Hospital in Paddington, west London.
Twitter coverage of the Toronto Marathon is at: @RunCRS
The race begins at 1.45pm UK time.
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