verb
maintain
mayn-TAYN/meɪnˈteɪn/
To keep something supported in an established condition.
The mechanic maintains the bicycle by carefully oiling its chain.

Etymology
The underlying image is holding something in the hand. This became supporting or preserving it, then keeping it in an existing condition or ensuring that support continues.
In context
and it has a lot of strong muscles to give it some support So this isn't putting a lot of unnecessary strain on my hip and it's allowing me to maintain a neutral spine position
More examples
- The thermostat maintains a steady temperature.
- She maintained her balance on the slippery sidewalk.
- Maintaining a regular sleep schedule helps me feel rested.
Forms
maintain · maintains · maintained · maintaining
maintenance noun — Work needed to keep something functioning well.