Get fit in London, and do something for your Country! It's easy, it's the fitness sensation sweeping the nation (no, it's not pole dancing). Run around Parliament Square, wearing your favourite protest t-shirt.
Personally, my route was from the south/east end of Lambeth Bridge, up to Westmister Bridge, over and around Parliament Square, up Whitehall, down Northumberland Avenue, over Hungerford Bridge, past The Eye, back over Westmister Bridge, down Millbank and back over Lambeth Bridge.