Low angles during acceleration are a product of greater horizontal force requirements. The lower(angularly) you apply the force proportionally the less vertical force you get. Obviously there is a requirement for vertical forces to achieve the desired height of CoG. So the lower you get, proportionally you must exert a higher force in order for that proportion of vertical to be sufficient to raise the CoG and not stumble all over the place.
That force is generated from the hips during extension and maintained through your core.