Usually run in the woods and manage fine but my 8 year old (who plays football for a local team)son has shown an interest. Brilliant I thought so along he came. He did well but too many obstacles for a boy who is accident prone. So I suggested running round a field thought I could take the rest of the football team and get their fitness up also encouraging me out but running on the field was so hard I didn't even manage 8 mins. ( I am on wk 9 so should be running 30 mins). What shall I do?