Is this the most unexpected proposal ever? She thought he was just stretching his legs!A London Marathon runner has made his day even more memorable by proposing to his girlfriend during a routine rest stop.

This video, posted to Facebook by a family member, shows the heartwarming moment Jordan Meikle pops the question to girlfriend Kayleigh Harris on the sidelines of the marathon route.

At the start of the clip, Jordan is casually talking to Kayleigh while he fumbles about in his pockets and bag - facing away from her so she can't see the ring.

He then starts to stretch his aching muscles. But he takes his lunge just that little bit too far and his knee hits the floor, putting him in prime proposal position.

Poor Kayleigh doesn't seem to realise what's happening. That is, until she sees him open a box and present her with a ring.Cue lots of screams and congratulatory cheers from the crowd before Jordan sets off on his way again - after a quick kiss from his new fiancee.

This proposal comes on the same day a couple tied the knot halfway through the 26.2 mile endurance test. Newlyweds Laura and Paul then faced another gruelling 13 mile run before they could enjoy their wedding reception.

Congratulations to both couples!

London Marathon proposal: Watch runner break off from race to pop question to girlfriend, London Marathon (Recurring Competition), Wedding, Session, Television