A behavioral analysis of diaphragmatic breathing and its effects on peripheral temperature.

Three young women volunteers were trained through instructional feedback in two breathing procedures: diaphragmatic, derived from Eastern meditative techniques, and thoracic, involving opposite maneuvers. A single-subject reversal design was employed. Physiograph recordings of diaphragmatic expansion and mouth breathing provided the basis for feedback. Peripheral (digital) temperature was time-sampled at 1-min intervals and linear regression lines were fitted to the data. Temperature decreased throughout "normal" (baseline) breathing, probably due to warm outdoor and cool indoor temperatures. For two subjects, temperature during diaphragmatic breathing was generally stable; temperature during thoracic breathing showed significant decreases and did not differ from normal breathing. Within-session reversals showed dramatic changes in temperature as a function of breathing technique, which were maintained at follow-up, for these subjects. Temperature was more labile and decreased regardless of breathing procedure for the third subject. These data support a relationship between respiratory and vasomotor activity, and suggest that breathing strategy may be an uncontrolled variable in temperature biofeedback. It is further suggested that diaphragmatic breathing may facilitate temperature biofeedback or other types of relaxation training.