To express hip flexion mobility and lower quarter/core stability in a drill to support running technical development.
As per the video, hug a knee to the chest, lifting yourself up onto the forefoot, then stepping down to switch sides.
Continue for 10-20 metres
Foot strike should be midfoot - picture a big red button under the midfoot - hit that red button when the foot hits the floor.
The triple flexed leg should have dorsiflexion (imagine a bucket of water being hung from the toes/forefoot - if you plantarflex, you lose the bucket)
Squeezing the thigh towards the chest creates a core activation - upper quarter pull through the trunk connecting to the lower quarter. This facilitates trunk stability and pelvic stability whilst expressing hip flexion mobility and drilling stance leg dynamic stability.
Common errors and corrections:
Foot strike is at the heel, then rolls on to the forefoot - correct this by stepping much shorter.
Foot strike is at the forefoot, but too far out in front, such that the foot lands in too much plantarflexion, causing a significant drop at the heel when weight is accepted - correct this by stepping much shorter and cueing to maintain dorsiflexion right up to foot strike.