Water droplets supposedly act like magnifying glasses and scorch leaves. In 2010, Hungarian physicists put this gardening lore to the test. On smooth maple and ginkgo leaves, droplets caused no burns: the point where they focus sunlight usually lies well beyond the leaf. The exception is very hairy leaves, which hold spherical droplets above their surface. Watering in the morning still makes sense, but to cut evaporation.
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.