Well, that's true - it's essential to be in good shape prior entering the gym, otherwise your dream training might turn into a slightly bad experience. But, don't worry I'll reveal you how to avoid such situations with a few exercises that will prepare you for the bigger challenge.
The following program is designed to show and improve your current fitness level. It consists of indoor and outdoor training without using any weights. Here are the exercises:
1. Chin up
Grab the bar firmly at the shoulder width, cross your legs and start rising your body up. Try to keep your elbows perpendicular to the floor.
Go to the parallel bar and rise until your hands are straight. Then flex your elbows and go down until your elbow and upper arm are perpendicular. Raise again to the initial position.
3. Inverted parallel row
Use the parallel bar to place your feet on the two separate bars and let your body sink. Grab the handles and start flexing up. This exercise is a sort of inverted push up.
4. One leg Bulgarian squat
4.1 Start sitting and standing up on one leg from a chair. The other leg stays straight forward. Repeat until you can make the move without the chair.
4.2 Place your right leg foot parallel on a chair. From that position start squatting. Keep your posture straight during the exercise.
4.3 Take a smaller chair and start climbing up and lowering down while alternating your legs.
5. Hanging leg rise
Grab the bar with arms and hang. Then slowly rise your legs until your ankles reach you chest. Make a short pause and continue.
6. Vertical leg crunch
Lay on your back with hands close to your body. Start raising your legs to the chest until they are perpendicular to the floor. Next lower them slowly till they are 5inches from floor. Don't bend your lower back during the exercise!
7. The plank
Take a push up position, but with your elbows on the floor. Try to hold for a 120 seconds.
8. Push up
Start from a normal push up position with palms and toes on the ground, and keeping a straight line from your heels to shoulders, place your legs on a chair or swiss ball. From that position bend your elbows down until your chest reach the floor. Then quickly go up into a initial position.
The preparatory exercises are designed to be used with 3 sets by 8 repetitions or 3x12reps. Know that you are ready for the gym when they cause you no huge effort.