This is due to bad posture while sitting, i.e., bad posture in the seated position. Those big soft multi-sectional leather sofas are often the cause of this reaction.
The muscles are forced into an awkward posture usually with the butt sunk into the seat and the upper body is laterally crooked and vertically forced to curve concavely while seated.
When one gets up, the muscles have to readjust to a standing position to straighten and support the skeletal frame. The muscles thus have to tighten up from the awkward posture of the “relaxed” muscles. Since the muscles had to adjust themselves to the contour of the sofa, they now must readjust themselves to provide support for the skeletal frame for getting up and standing. This readjustment of the muscles is done by tightening up.
Instead of those big sectional leather sofas, one can change to individual reclining sofas.