Liquid Diet

Hi,

Okay I've searched about this a few times, and it seems it's not
recommended but I must do it.

I need to sometimes go on an all liquid diet for about 48-60hrs
straight during the week, because if I don't some of my stomach
problems will pain so bad, and I won't be able to conscentrate on tests
and things like that.

The type of liquid I drink during this time is easy to digest stuff,
mainly juices and water.

What I want to know is if it's okay go to the gym at this time and lift
and do some cardio (jogging, treadmill, etc.). I'm not looking to gain
much muscle mass, I just don't want to lose any. I do hope to lose some
fat though.

Thanks,