Don't move the middle: bear crawl with small plate (part 3 of 5)

The bear crawl with small plate is part 3 of the 'don't move the middle' core strengthening series.
The idea is to crawl forward 5-10m on your hands and feet with a stable torso parallel to the ground throughout.  The tricky part is to keep your hips down, and this can be achieved by bringing your knees through outside the elbows.  View the clip below to get a sense of the exercise. 

video: bear crawl with small plate