Calling all marathoners: tell us why you ran!

If you were among the 36,000 runners who ran London Marathon last Sunday, we want to know why! Did you run for charity? If so, why did you pick that one, and what does it mean to you? Send us a short video (you can film it on your smartphone) and submit via our free app, and you could win £100.

You can download GuardianWitness here and find out about other assignments here.

Thanks to guardian.co.uk who have provided this article. View the original here.