SWINGEROliScarff:Getty

Pensioners exercise in London's first purpose built 'Senior Playground' in Hyde Park on May 19, 2010 in London, England. The playground, which cost 50,000 GBP, features six machines: a cross-trainer, sit-up bench, body-flexer, free runner, flex wheel and an exercise bike. By Oli Scarff/Getty Images.

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