Table 4.

The mean increase in both the groups.

Groups	Resting volume (ml)	Placebo effect (ml)	TENS stimulation (ml)	Mean increase (ml)
PM + OD	0.60 ± 0.61	0.60 ± 0.61	0.93 ± 0.89	0.33 ± 0.27
PM − OD	3.40 ± 1.06	3.32 ± 1.07	3.86 ± 1.15	0.46 ± 0.1
P value	<0.001	<0.001	<0.001	0.031