I like to plan my training in periods of about 4 weeks – nothing magic with this number (…I believe…) but for me this currently seems a good balance between seeing some real progress, and not getting bored. I also have read somewhere that after about 4 weeks doing the same you’ll plateau, but I dont fully buy that. I believe this enormously depends on the thing you are training, and how you are training it.
When I say “plan” it does not mean that I put together a four week plan. It is more about defining the areas I want to focus on during this period – but I will still do a bit of everything on the side, CrossFit style. I believe you can’t focus on too many things at a time, so I’ll generally have two “tough” goals that require actual work and exhaustion to get there, and two “skill” goals that are more playful. An example for “tough” goals is to improve the squat, or the CrossFit Total, or my metabolic conditioning (generally or within a certain horizon such as “2min max effort”). An example for a skill goal would be to master the (foundation of) the Olympic lifts, or the Handstand.
When then putting my workouts together – which I tend to do on the day, or the evening before – I know that I will have to emphasise my focus areas whilst making sure that the other one’s still get some room. So typically a workout would at 50-70% focus, the remainder being general skills.