The acid may spill onto the posterior region of the larynx. The mucosa in this region can become irritated and pathological conditions may develop. Reflux has been identified as an etiologic factor for chronic throat clearing, contact ulcers, laryngitis, cancer, granulomas hoarseness and other disorders of the larynx. This and other factors have potential to reduce phonation threshold pressure. A cool-down is a gradual reduction in activity.
Blood vessels remain somewhat dilated, providing oxygen-rich blood.
The oxygen facilitates removal of lactic acid and speeds recovery. When the cover of the vocal folds is relatively dehydrated, the phonation threshold pressure becomes higher. Additionally, caffeine is a central nervous system stimulant. This effect on the CNS could sabotage therapeutic efforts that encourage relaxation. Finally, caffeine can aggravate reflux because it weakens the lower esophageal sphincter.