Extra time: how smart exercise keeps you younger for longer

Creaking knees, stiff back, dodgy shoulders… Age is no friend to the human body. So how are veteran athletes like Roger Federer and Jo Pavey still at the top of their game? And what can you do to keep up?Slow down, that used to be the mantra for middle age. The dread half-century reached, fiftysomethings were expected to take up less challenging physical activities – if they were physical at all. A gentle stroll around the golf course, perhaps, rewarded with a gin and tonic at the 1