A different lunge variation, this time, we’re going out to the sides. Runners never really move in the lateral (side-to-side) plane – we just move forward and back. That’s a problem because we need to be able to dart around human traffic, holes in the road or dogs who run in our way, and if we don’t train in all planes of motion, we run the risk of picking up an injury.

As well as strengthening our butts and ankles, cossacks really work the inner legs – our adductors and abductors.

How to:

Standing on your left leg, take a big step out to the right.
As you step out, bend the right leg and sit back as if going to sit in a chair.
You want your left leg to remain straight while your right is bent, making sure that your knee doesn’t come over your right toes.
Push off on the right foot to stand tall, and go again.
Try six reps on one leg then switch.

Strength training for runners: 5 single-leg moves every runner needs to do weekly