An article from the best Personal Trainers Tustin has to offer

Last time I wrote, I clued you in to a few exercises that can allow you to use your own mass to weight train your upper body and abs. But it doesn't stop there. There are a few neat exercises that allow you to work out your lower body as well without even touching a weight plate.

The one legged squat is sometimes called "The Pistol." It not only works your legs, it develops your balance as well. To start, get your balance on one leg and raise your other leg straight out in front of you, making it as parallel to the ground as you can manage. While keeping your standing foot flat on the ground, lower yourself as far as you can go, and stand back up. While doing this exercise it usually helps to extend an arm in front of you to maintain your balance.

Squat thrusts are a great explosive exercise that are especially helpful to those who play sports. To start, simply stand up straight. Now squat down and rest your hands on the floor. Keeping your hands where they are, jump your feet back behind you and get into the push up position. Rapidly move your feet back up into the squat position, and stand up. Do all of these motions quickly and rhythmically. It will help you get some cardio as well.

The walking lunge is a classic no equipment exercise that works best if you have a large room to work in. Start in the standing position, and take and very big step. When you put you put your foot down, lean into the step so your front leg is at a ninety degree angle and your back knee touches the ground. Lift yourself up, and repeat with the other leg. When you get to the other side of the room, turn around and keep going.

Of course, these aren't designed to take the place of your usual personal training routine. They're just neat to have in mind if you are ever in a pinch. Check with your personal trainer if you are ever temporarily going away from you gym for information on the best ways to stay fit until you get back.