then should you try adding extra runs on other days and never double up on more than four days a week. And remember, back off if your pace drops or you start to feel unduly tired or sore.Steve Smythe, RW Race Services Editor, runner for 30 years
.Run variedWhile there are thousands of speedwork variations (top British coach Alan Storey claims never to set the same session twice), most runners tend to stick to their tried and tested stock sessions. One week 400s, next week 800s, the following week