Climbing is a full body, closed chain workout that allows the user to make real choices. Here is a basic 3-rep sample that builds upper body and core muscles in 3 decreasing reps, from larger to smaller muscles.
Begin with an overhanging angle and use the easiest route or the largest holds to climb 60 feet, remember to push off your feet to transfer weight to your lower body. Maintain control of your core and your balance to achieve full body control instead of overly stressed fingers. Take a rest, shake out your arms, and then decrease the angle slightly.
Begin a 40 foot climb using slightly smaller holds, concentrating on good foot placement. Pick a route that has a variety of movements so that you can go slowly and powerfully throughout your full arm movement while focusing on your upper body. Take another rest, shake out your arms.
Decrease the angle again, and climb 20 feet using the smallest holds, optimizing every foot placement for strength. These smaller holds will focus the stress in your forearms and calves.
For harder workouts lengthen distances and increase the angle on the machine; but go slowly when starting, train with a partner and alternate climbing and resting. Your tendons will take all the strain until your muscles develop, so start slowly and stretch frequently.