Recently Runners World published in it’s magazine an article on strength training for runners. 

The article can be found here.

Among some of the exercises suggested are:

Bridge:

Plank lift:

Side Plank:

In his blog Matt Fitzgerald also has a list of exercises you can do to strength train as a runner.

He recommends similar exercises as Runners World but adds some more. Like:

Dead Bug:

 

Single leg squat:

You can read the whole article in his blog.