When I say springs, I mean the simultaneous timing between the hips and the knees.
Biomechanically they are the main shock absorber in the body. If we are running, we need a good soft hip and knee to absorb the force from the ground as we land onto it with one foot, we then use the recoil to easily push forwards to propel us forwards in our running cycle.
Think now what would happen in these natural springs were a bit stiff, or the timing was a bit out, something would still need to absorb the force of the ground but if the hip isn’t going to do it effectively the next best thing may be the back or the knee. How many people describe how they get back or knee pain when running or walking down hill? The symptom is the pain in the knee or back, but the cause is either led by the spinal posture or lack of absorbing force through timing between the hip and the knee.
Give this exercise a try….