RESULTS

Both groups ('yoga' and 'control') had approximately similar values of critical flicker frequency (CFF) on initial testing (group mean + SEM, 37.6 ± 0.7, and 37.9 ± 0.6, respectively). At the end of 10 days, the CFF of the yoga group had significantly increased to 42.6 ± 1.6 (p<0.01, Wilcoxons paired signed ranks test), whereas the control group showed no significant change (38.4 ± 0.7, p>0.5, Wilcoxon's paired signed ranks test). The final value of the yoga group was also significantly more than that of the control group (p<0.001, t test for unpaired data).