That means walking. Walk on the floor of your bedroom. Even if you have very little space in your house. Don’t despair! Just make a circle and walk circularly, suppose, in a space of 4 feet by 4 feet! If that space is not available go for free hand exercises like on-spot jogging type, sit-ups, just to move your limbs for greater blood circulation! Where there is a will there is a way. Don’t relent.