It is excellent for your health to consciously stretch when you yawn, much like cats do.

noli's read

This behavior, scientifically termed pandiculation, is a natural reflex observed in many vertebrates. Neurophysiological studies suggest that pandiculation helps reset muscle tone and stimulate proprioception after a period of inactivity. Although the idea of imitating a cat is a common analogy, research (notably work published in journals like 'Frontiers in Neurology' regarding yawning) primarily highlights the role of this reflex in alertness and cerebral thermal regulation. The term 'excellent for your health' is broad: stretching is beneficial for flexibility and physical comfort, but there is no robust evidence specifically isolating the stretch associated with yawning as a miracle therapeutic practice. The statement is therefore a positive interpretation of a normal physiological reflex. It is fair to say that following this natural urge promotes better awareness of one's body.

the sources

No named source held this one up — that absence is part of the verdict.