Table.

Respiratory frequency and variability, and sensitivity of baroreflex, in 23 healthy adults. Values are means (SDs)

	Respiratory frequency (breaths/min)	Respiratory variability§ (%)	Baroreflex sensitivity (ms/mm Hg)
Spontaneous breathing	14.1  (4.8)	21.6  (4.5)	10.5  (5.3)
Controlled slow breathing	6.0 (0.01)	5.4 (0.7)**	13.2 (6.6)*
Free talking	7.6 (2.4)***	37.4 (2.2)**	9.5 (4.6)
Ave Maria	5.6 (1.1)***†	8.3 (1.8)**‡	11.5 (4.9)†
Mantra	5.7 (0.6)***†	6.2 (0.7)**‡	12.3 (3.6)†

^*P<0.05, ^**P<0.01, ^***P<0.001 v spontaneous breathing; ^†P<0.05, ^‡P<0.001 v free talking. 

^§Coefficient of variation (SD/mean×100) of respiratory frequency, for each subject during each recording.