Subjects and Training: 40 student volunteers of either gender studying in 8th standard at Government Higher Secondary School, Indira Nagar, Pondicherry were motivated and recruited for the present study. They had no previous exposure to yoga training and none of the subjects had a history of substance abuse. Respiratory and cardiovascular diseases were ruled out by their history and clinical examination. Their age was 12 to 15 (13.21 ± 0.10, SEM) years, weight 20 to 57 (34.97 ± 1.24, SEM) kilograms, height 1.3 to 1.66 (1.48 ± 0.01, SEM) meters and body mass index (BMI) 8.33 to 23.30 (15.90 ± 0.44, SEM) units. After briefing about the study protocol, informed consent was obtained from them as well as their parents. The subjects were divided randomly into two groups of 20 each.

Group I (yoga group) : Group I subjects were taught the following asans and pranayams: talasan, utkatasan, trikonasan, ardhamatsyendrasan, bakasan, pavanmuktasan, navasan, noukasan, matsyasan, pashchimottanasan, halasan, bhujangasan, shalabhasan, sarvangasan, shavasan, mukh-bhastrika, mahat yoga pranayam, nadi shuddhi and savitri pranayam. Each pose was held for 30 seconds and a short period of rest was given between the poses. Each pranayam was performed nine times. Shavasan was performed at the end for ten minutes. Detailed description of these techniques is given in standard texts on yoga (13, 14).

The subjects underwent yoga training over a period of 2 weeks. After the training period, 45 minute practice sessions were held regularly, Monday through Saturday, for a total duration of 6 months under our direct supervision.

Group II (control group) : Group II subjects did not receive any yoga training. They were asked to study in a classroom while Group I subjects were undergoing yoga training.

Parameters: : 2-3 days prior to pre-training recordings, the subjects were familiarized with the laboratory environment and their anthropometric measurements were taken. They were given instructions about the experimental procedures and practice trials were administered until we were satisfied that the subjects performed the test as required of them. Pre and post training measurements were taken about 2 hours after a light breakfast.

Handgrip strength and endurance: HGS (mm Hg) was measured with the dominant hand gripping an inflated cuff of a mercury manometer while the subject was sitting comfortably in a chair. The arm was extended in front at the shoulder level and kept horizontal to the ground. For determining HGE, the subject was asked to maintain 1/3rd of HGS in a sustained squeeze for as long as possible and the time (sec) was noted. In all our subjects, right hand was dominant hand. Dash and Telles (8) have reported that hand grip strength of right hand is greater than that of left hand.

Respiratory pressures : MEP was determined by asking the subject to blow against mercury column of a manometer after taking in a full breath. The maximum level at which the mercury column could be maintained for about 3 sec was noted. MIP was determined by asking the subject to perform maximum inspiratory effort against the mercury column after breathing out fully. MIP that could be maintained for about 3 sec was noted. It was ensured that the subjects did not use oral muscles to develop pressure or tongue to block the tubing.

Spirometry : FEV, FEV1 and PEFR were measured by computerized spirometer (Spirocheck, Morgan, England). The subject was instructed to take maximum inspiration and blow into the mouthpiece as rapidly, forcefully and completely as possible. It was ensured that a tight seal was maintained between the lips and the mouthpiece of the spirometer.

The above mentioned parameters were measured before and after the 6 months study period in both the groups. For each parameter, three trials at three minute intervals were given and highest of the three values was used for statistical analysis.

Statistical analysis: The data was analyzed using Student’s paired ‘t’ test to compare the pre and post training values of both the groups. P value of less than 0.05 was accepted as indicating significant difference between the compared values.