Motion is even and fluid, the muscles neither stiff nor rigid.

With every muscle rigid, The Shadow listened in that dark lower hall.

The layers of rigid muscle knotted much too tight for comfort.

She shook herself again, tried to relax the rigid muscles of her body.

He had the progressive nerve disease, which causes tremors and rigid muscles.

The rigid muscles in his shoulders relaxed under her hand.

He felt his rigid muscles soften like parched earth beneath drops of cool water.

He was just as pale as his brother, every muscle tense and rigid.

"No," she shot back, defiance and indignation in every rigid muscle.

By her cold, waxen skin and rigid muscles, she had died many hours ago.