Horses. People. Both powered from below and behind. Your body’s largest muscles are at the back (just take a look back there!) but with eyes in front, so we tend to lean forward. Forward leaning tenses the front of the body. Try it. Can you feel it?
Focus on depth: balance your body front AND back. Stand and rock your body front to back. Then imagine a dinosaur tail down your neck, back, extending on the floor behind you. This is a strong T-Rex-y tail, so lean back and feel your front relax.
Relax, your back has got your back.