Don't inhibit this. Pressing is unhealthy and must be transformed into the more natural motions of pulling and lifting. The breath test, comparing the ability to breathe deeply in different positions, is a great indicator of when you are playing in a more natural position. This can be achieved with sloped cello cushions or chairs. You will notice that your arm weight seems less when you do this.
Back problems are most common in cellists, harpists, and pianists.
The idea of holding the cello in the center of your body comes from the old end-pin days. Align the cello with the left side of your body, keeping it away from your neck and shoulder. The body naturally moves in curves. The right hand naturally moves in a counter-clockwise direction. The bow hand should travel in a figure-8 pattern when bowing.