I didn't submit the picture to Runner's World, so I haven't waived any rights. I've now found out that a friend of a friend sent it in and I have emailed Alice asking about the use of my photo in these circumstances but received no response!
I hope everyone takes note of that section from the T&Cs - by uploading photos on this site you are waiving all copyright in them and RW can use them in their own promotional material with no credit or royalties to you. I suggest you don't upload any photos on this site unless you're happy to be working as an unpaid RW photographer!
Thanks everyone for the positive comments on it anyway.