PRANAYAMA INCREASES GRIP STRENGTH WITHOUT LATERALIZED EFFECTS
P. Raghu Raj J, R. Nagarathna, H. R. Nagendra and Shirley Telles*
Vivekananda Kendra Yoga Research Foundation
No.9, Appajappa Agrahara,Chamrajpet, Bangalore - 560 018
(Received on July 17, 1996)
Abstract: The present study was conducted to determine whether breathing through a particular nostril has a lateralized effect on hand grip strength. 130 right hand dominant, school children between 11 and 18 yrs of age were randomly assigned to 5 groups. Each group had a specific yoga practice in addition to the regular program for a 10 day yoga camp. The practices were: (1) right, (2) left, (3) alternate- nostril breathing (4), breath awareness and (5) practice of mudras. Hand grip strength of both hands was assessed initially and at the end of 10 days for all 5 groups. The right, left- and alternate- nostril breathing groups had a significant increase in grip strength of both hands, ranging from 4.1% to 6.5%, at the end of the camp though without any lateralization effect. The breath awareness and mudra groups showed no change. Hence the present results suggest that yoga breathing through a particular nostril, or through alternate nostrils increases hand grip strength of both hands without lateralization.
Key words: unilateral nostril breathing; hand grip strength; yoga: lateralization.
The nasal cycle is an ultradian rhythm characterized by alternating patency of the left and right nares, with a periodicity of two to eight hours (1). The two (right and left nostril patent) phases have been correlated with the activity and rest phases, respectively of the basic rest activity cycle (BRAC). It was described (2), how another primitive rhythm of "hunt (and eat) then rest" has also been coupled with the BRAC. At hunger contraction periods (the 'hunt - and eat' phase) the power of hand grip (tested with a grip dynamometer) is greater than at the quiescent or 'after dinner periods'. This suggested that the former phase correlates with the activity phase, while the latter correlates with the rest phase. There is no report regarding whether the hand grip can be correlated to the phase of the nasal cycle. However it was speculated (3) that right nostril breathing would increase the grip strength while left nostril breathing would have the reverse effect.
Certain yoga breathing practices which involve breathing exclusively through a single nostril, allow the effects of single nostril breathing to be checked, as these practices can be carried on effortlessly for prolonged periods.
In the present study the effects of these yoga breathing practices on hand grip were considered worth investigating based on the above mentioned facts as well as two more, viz., (i) unilateral forced nostril breathing has been reported to cause contralateral cerebral hemisphere stimulation (4), and [ii] it was shown (5) that difference in hand grip between the two hands are related to the relative functioning of the two cerebral hemispheres.
Hence the present study was designed to compare the effects of ten days of each of four yoga breathing practices, i.e. selective right nostril breathing, selective left nostril breathing, alternate nostril breathing, breath awareness without nostril manipulation, on the hand grip of both hands separately. It was aimed at finding out whether there was any lateralization effect (e.g. with right nostril breathing, right hand grip changes or whether a contralateral effect is observed). There was a fifth group which practised certain hand gestures (mudras). This was considered necessary as the pranayama practice in specific yoga exercises, i.e. sav, cav, and nds groups is associated with specific mudras. These practices involve keeping the fingers in specific postures, which could possibly influence hand grip strength.