Choosing how far to go for the weekly long run on your training plan can be challenging - especially for the newer runner. And more so when you are preparing for your first ever 50k.

Make the run too short and you won't get sufficient aerobic fitness from the run. Likewise, if you make the run too long, then your running form will start to "break down" as you become more fatigued.

In this video I explain what your options are for getting the miles in - including a valuable lesson from the Kenyan elite athlete squad.

How do you go about choosing the distance of your weekly long run? Or do you follow the advice of your coach?