Here is a poem I wrote a few months ago about running:

its a feeling you can’t explain

when you’re running

                and running

                                and running

and you’re just about to hit your physical limit

 then you see the finish line in the distance        

you push harder

harder than you thought possible           

and you struggle and push some more 

until suddenly you’re done

 your breathing slows    

 the feeling of nausea fades       

 the side cramp subsides

and a new feeling invades

one of satisfaction,

                accomplishment

and you say to yourself

                I              

                    Did

                        It