Which child am I?

I found this image of my school sports day at the Old Merthyr Tydfil website and was amazed to see myself on there. I think I might have been about 10 at the time. I have no idea who sent the picture in or any recollection of that particular race. However, what I do remember is I never used to win. There were always better sprinters than me. I used to try very hard though. I never came last probably somewhere half between.

I think I reached my peak with school sports at the age of 15. I was a good cross country runner and not too bad at the high jump and hurdles as well. In 1976 I was due to captain the red house team for the girls [Caradog House], but alas, I never got my moment of glory. As my father was a postman, we used to take our holidays at different times and often I would have to take a week or two off school for the family holiday.

Now the question is...which girl am I on the picture? [Click on picture to enlarge]

I'll give you a clue: I'm the one with a very determined look on her face!