His erect posture slowly stiffened as every muscle in his body surged to alert status.

Anger flashed momentarily in Blackjack's eyes, and his posture stiffened.

Coughlin's posture stiffened and his tone became more pedantic.

Eden's posture stiffened at this rather alarming disclosure.

His posture stiffened, and the light fled from his eyes.

He stopped working, and his posture stiffened.

Without hardly being aware of it, her posture stiffened and her smile grew empty.

Odo's posture stiffened against the back of his chair.

Talev's smile faded and her posture stiffened in response to the comment.

My posture stiffened, and I tugged my blanket up when it slipped.