Its definitely worthwhile shaking up your routine every few months or so: this helps keep your interest and motivation levels up, break training plateaus and gives your body different types and styles of workloads to adapt to.
Many lifters now train with a 2 or 3 day split routine which are brilliant for working selected muscle groups on one day whilst letting others heal and repair for an extra day or two before being worked again.
This lifting format is great as long as you are able to training consistently each week, but missing workouts can cause things to slide very easily as the training pattern suddenly gets out of sync.
If you feel its time for a change or perhaps making time to strictly follow a split routine is becoming difficult due to other commitments, why not try a full body workout. These can be completed within an hour quite easily and repeated several times each week or if time is tight just once or twice.
METHOD: select one exercise per muscle group and go heavy (after warming up of course) by completing 3 sets of 6 reps, rest no longer than 60 seconds between each set. Once you have completed 3 x 6 for one muscle group, move straight to the next and go again.
This will enable you to work your whole body in under an hour whilst burning off many calories as a result of the training intensity being employed.
If you are stuck in a training rut or just fancy a change of workout, identify some key exercises and give this a try!