Favourite Running Strength Exercises & Stretches

A friend and I have started a free online resource for runners.

The idea being that we upload a new 15min running strength, flexibility, and core, workout every day, with full instructional videos.

N.B. We are happy to share the link to this resource if people are interested... Just ask! We have intentionally omitted the link at this point as we don't want to be accused of misusing the RW forum, even though the resource referred to is free 

We'd like to know what exercises everybody has found most beneficial to their running.

Which exercise, drill, stretch, etc... do you swear by?

Calf raises and lunges, lunge with back leg elevated with weights where you go up and down, leg press, stability on balance board or cushion. Also variety of plyometrics, jumping up onto a box and jumping down, with hands on a bench jumping over the bench from side to side, sit ups.