Ill be going to Europe for 3 weeks the 11th, Ive been giving my body time off from lifting, 3 days now. My question is when I come back will I be at a loss for taking so much time off. I plan on doing push-ups pull-ups sit-ups and the like, will this help keep my losses to a minimum. Also what are some other exercises I can do without weights? Thanks for the help.

Burpess, lunges, wall squats, pistol squats etc

You might lose a little strength i wouldn't worry about it too much.