The WHO recommends that 5 to 17-year-olds get at least 60 minutes of moderate to vigorous activity a day on average, plus muscle and bone-strengthening activities three times a week. Yet more than eight in ten adolescents worldwide fall short. Running, climbing, jumping, walking to school: active play is the best sport there is.
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.