these should be started gradually like all the exercise the first time you try it do it only once or twice then repeat after a few hours, this time increasing the count to three or four after a few days to the exercise 10 times in succession.
2. a similar exercise also for strengthening the eyes was rolling the eyes in all directions.
3. Other exercise for outdoors in the sunshine is looking at the sun but blinking very rapidly then repeating the process with the other eye, this keeps the lens of the eye functioning properly.