1) See if you've got a local 'Gym' near you:
2) Get a free gym pass code from (these change each day/week, so come back another day if your local isn't on there atm)
3) Follow details and you will get a unique code to enter when arriving at the gym.
4) Repeat each day and book for following day (some people have been getting free gym for several months now).
Not tested, but certainly worth a go.