As Billy Connolly once said: There's no such thing as bad weather. There's only the wrong clothes.
Determined and experienced ramblers properly kitted up will laugh in the face of changeable weather, as will canoeists, surfers and wild swimmers. In some activities, you're going to get wet and cold anyway, so a bit of extra weather doesn't matter.
This is good weather, too, for sports that really exert you, such as football, running and competitive cycling. No one likes pedalling into a gale, but a burst of rainfall can be a relief when your body temperature is high.
Sports involving hand-eye co-ordination or grip aren't helped by changing weather, so you'll probably prefer to head to the leisure centre for racket sports or climbing. Squash, badminton, basketball, volleyball and indoor climbing let you work up a sweat whatever the weather is doing.
Mixed weather can make gardening more fun. Hard work outdoors, like digging, is made more bearable if there's a strong breeze or the occasional shower to cool things down. And if you don't fancy venturing out at all, it might be a good time to concentrate on home improvements. Painting walls and ceilings is great exercise, as is plastering, sanding or doing the hoovering and other housework.
Craig is one of Britain's top gardeners and Head Gardener at River Cottage. He gives his top tips for looking after your garden or allotment during the summer.