A new diaphragmatic breathing technique practiced without the aid of a physical corset is outlined, and the findings from a study of its application in the respiratory rehabilitation of asthmatic patients are presented. Sixty-seven asthmatic adults randomly assigned to either deep diaphragmatic breathing training, physical exercise training, or a waiting list control group participated in a 16-week program. Deep diaphragmatic training resulted in significant reductions in medication use and in the intensity of asthmatic symptoms. Importantly, a nearly 300% increase in time spent in physical activities also resulted from deep diaphragmatic training. A follow-up at two months found many patients had returned to earlier medication levels and sedentary habits. A strengthened musculature can replace the need for a physical aid in this respiratory habilitation; adherence to its use may require individually-tailored encouragement.