Not sure that would really be your style? Well, the president of the Basque Naturist Association made a compelling case when she told the BBC: "Doing sport without clothes is natural - and much more comfy."
Not everyone is convinced:
Sceptics suggest that running full tilt in the buff might not be entirely enjoyable, though. Sports underwear, they point out, was invented for a reason.
But the gym owner denies her concept is impractical.
"Being a naturist doesn't mean being daft. If a woman needs to, she can put a top on!" says Merche Laseca. "But there's cycling, weightlifting and the Stairmaster: there's lots you can easily do naked."Story from: