Beneath the glass of an induction hob, a coil carrying alternating current creates a magnetic field that flips tens of thousands of times per second. In the base of a pan made of magnetic metal, this field induces electric currents that heat the pan directly. The glass only warms up through contact with the pot. To test a pan, just use a magnet: if it sticks to the base, it will work.
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.