Q:

How would you acheive a full body workout in a bare cube room?

Scenario: You are stuck in cube room. The room is completely bare. It is 10 metres by 10 metres by 10 metres. There are no weights of any kind in the room. The room is well lit and ventilated. You have access to an infinite amount fruit,vegetables,herbs,nuts, and water. (You also have access to toilet facillitys however you cannont use them in anyway as a surface to preform any form of exercise)
Objective: To work out all the muscles given the restrictions of the Scenario.
What I want to know(regarding the Scenario Given):
Q1.-Can I achieve a full body workout?
Q2.-What muscles would be the hardest to build? (Given the scenario)
Q3.-What exercises are the best exercises available for those muscles? (Given the scenario)
Q4.-What muscles would be the easiest to build? (Given the scenario)

A:

So your scenario calls for body-weight training without objects (other than maybe walls).
There are a ton of resources on body-weight training available for you on the internet. I will not even start to describe them.
Q2: I would say the hardest ones will be muscles used for pulling, as you will have nothing to pull. I am thinking about back muscles and biceps.
Q3: Maybe bridge exercises for the back.
Q4: Easier muscles to build would be most others: "pushing" muscles like chest muscles, as you can always push against the floor, stabilizing muscles like abs with all sorts of planks, leg muscles with running, squatting and jumping...

