Normally we blink about 15 times a minute, spreading tears across the eye's surface. When focused on a screen, that rate drops by half or more, leaving eyes dry, stinging and red. Make a point of blinking on purpose now and then. Placing the screen slightly below eye level also reduces how much eye surface is exposed to air.
Chlorine on its own is fairly gentle. But when it combines with urine, sweat and other grime from swimmers, it forms chloramines, which cause stinging eyes and that classic 'chlorine smell'. A well-kept pool barely smells at all. Shower before you swim and never pee in the water.
Muscle mass slowly shrinks with age, putting independence at risk. But in 1990, a study had nursing home residents aged 86 to 96 train their legs for eight weeks: their strength more than doubled. Muscle responds to training at any age. Getting up from a chair without using your hands is already an exercise.