Abstract
(1) After 5gm. of creatine intake it produced a depressed effect on the ability of dark adaptation with rise in threshold. The effect varied in different individuals.
(2) After 5gm. of methionine intake it produced an improved effect on the ability of dark adaptation with lowering of threshold. The. duration of such effect lasted about 24-32 hours.
(3); The possible relationship between the effect of creatine and the effect after heavy muscular exercise on dark adaptation is suggested.
(4) The effects of creatine and methionine on the speed of visual purple regeneration and the ability of dark adaptation is discussed.
